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Volume 7014 Ground-based and Airborne Instrumentation for Astronomy II

Ian S. McLean, Mark M. Casali July 2008

Conference Location: Marseille, France Conference Date: Monday 23 June 2008

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Front Matter

Select this Article OPEN ACCESS		Front Matter: Volume 7014 Proceedings of SPIE Proc. SPIE 7014, 701401 (2008); http://dx.doi.org/10.1117/12.804485 Online Publication Date: Aug 04, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This PDF file contains the front matter associated with SPIE Proceedings Volume 7014, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.

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Instrumentation at Major Observatories I

Select this Article		Instrumentation at the W. M. Keck Observatory Ian S. McLean and Sean M. Adkins Proc. SPIE 7014, 701402 (2008); http://dx.doi.org/10.1117/12.788136 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Developing new instruments and upgrading existing systems continues to be an important part of our science driven strategic plan at the W. M. Keck Observatory, now in its 14th year of operation. Our emphasis remains on high angular resolution astronomy and faint-object spectroscopy. The instrument development program is now in its third generation. The first of these, OSIRIS, was delivered in February 2005 and together with NIRC2 is now in routine operation with the laser guide star adaptive optics (LGS AO) system on the Keck II telescope. During 2007 new wave front controllers were installed in the Keck I and Keck II AO systems and over 70 nights per semester are now allocated to AO science. WMKO is collaborating with the Gemini Observatory on the development of a solid state laser for the Keck I telescope. The V² mode of the Keck Interferometer is offered for routine observing and the 10 micron Nuller is now being used for the NASA exo-zodiacal dust survey key project. The atmospheric dispersion corrector (ADC) for the Cassegrain focus of the Keck I telescope was installed in 2007 and is now in routine use. In addition, a detector upgrade is under way for the red channel of the LRIS instrument on Keck I. Our next third generation instrument will be MOSFIRE, a near-IR multi-object spectrograph, which is currently in the fabrication phase. A Visitor Port on Keck I is now ready to receive instruments, with the first one expected to be NIRES, a cross-dispersed echellette instrument for the near-infrared. Deployment of a large suite of new acquisition, guiding and image quality monitoring systems to replace all the existing CCD guiders and acquisition cameras at the Observatory is also under way. The first system has been retro-fitted to NIRSPEC. Finally, studies are in progress on the development of a next generation AO system and an associated suite of instruments, and there has been a recent call for concepts for new seeing-limited instruments.

Select this Article		Instrumentation at the ESO VLT Alan F. M. Moorwood Proc. SPIE 7014, 701403 (2008); http://dx.doi.org/10.1117/12.786545 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract ESO's Very Large Telescope (VLT) on Paranal mountain in northern Chile comprises four 8.2m diameter 'Unit Telescopes' (also used for interferometry); four 1.8m movable outrigger telescopes dedicated to interferometry and two survey telescopes - the 2.6m VST to be used in the visible and the 4m class, infrared VISTA telescope. Here I will give an overview of the accompanying large instrument development programme which has so far delivered 11 operational facility instruments for the UT's (leaving one visitor Nasmyth focus) and 2 major instruments for the interferometric focus. In addition, a laser guide star facility has been added on UT4 to generate artificial (sodium) stars for the adaptive optics assisted instruments NACO and SINFONI; the optical and infrared cameras for the survey telescopes are almost ready; four major second generation instruments for the UTs (X-Shooter, KMOS, MUSE and SPHERE) are at various stages of development throughout Europe; a fifth (high resolution spectrograph capable of 10cm/s radial velocity stability at the incoherent combined focus of the four 8m telescopes) is the subject of a Call for Proposals; UT4 is being converted to a fully adaptive telescope and three second generation interferometric instruments (MATISSE, GRAVITY and VSI) have been approved following successful completion of their Phase A studies.

Select this Article		The status and future plan of Subaru Telescope instruments Hideki Takami Proc. SPIE 7014, 701404 (2008); http://dx.doi.org/10.1117/12.788254 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The first generation instruments of Subaru are seven plus one Cassegrain AO system. After the nearly ten year operation, the second generation instrument construction has been conducted. MOIRCS, 7' × 4' FOV NIR multi-object camera and spectrograph has been in operation from 2005, and is now most popular instrument of Subaru. A LGS AO system at Nasmyth focus (AO188) had the first light in 2006. HiCIAO; near IR high dynamic range coronagraph instrument working with AO188 for exoplanet detection had recently the first light. FMOS; fiber multi-object spectrograph with 400 fibers is now in commissioning phase. Hyper Suprime- Cam with 1.5 degree FOV at the prime focus is now being developed and will be in operation in 2012.

Select this Article		Current and future facility instruments at the Gemini Observatory Joseph B. Jensen, Scot J. Kleinman, Douglas A. Simons, Manuel Lazo, François Rigaut, and John K. White Proc. SPIE 7014, 701405 (2008); http://dx.doi.org/10.1117/12.789842 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract At the present time, several new Gemini instruments are being delivered and commissioned. The Near-Infrared Coronagraph has been extensively tested and commissioned on the Gemini-South telescope, and will soon begin a large survey to discover extrasolar planets. The FLAMINGOS-2 near-IR multi-object spectrograph is nearing completion at the University of Florida, and is expected to be delivered to Gemini-South by the end of 2008. Gemini's Multi-Conjugate Adaptive Optics bench has been successfully integrated and tested in the lab, and now awaits integration with the laser system and the Gemini-South AO Imager on the telescope. We also describe our efforts to repair thermal damage to the Gemini Near-IR Spectrograph that occurred last year. Since the last update, progress has been made on several of Gemini's next generation of ambitious "Aspen" instruments. The Gemini Planet Imager is now in the final design phase, and construction is scheduled to begin shortly. Two competitive conceptual design studies for the Wide-Field Fiber Multi-Object Spectrometer have now started. The Mauna Kea ground layer monitoring campaign has collected data for well over a year in support of the planning process for a future Ground Layer Adaptive Optics system.

Select this Article		Present and future instrumentation for the Hobby-Eberly Telescope Gary J. Hill, Phillip J. MacQueen, Povilas Palunas, Stuart I. Barnes, and Matthew D. Shetrone Proc. SPIE 7014, 701406 (2008); http://dx.doi.org/10.1117/12.788225 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Hobby-Eberly Telescope (HET) is an innovative large telescope of 9.2 meter aperture, located in West Texas at McDonald Observatory. The HET operates with a fixed segmented primary and has a tracker which moves the four-mirror corrector and prime focus instrument package to track the sidereal and non-sidereal motions of objects. The HET has been taking science data for nearly a decade. Recent work has improved performance significantly, replacing the mirror coatings and installing metrology equipment to provide feedback that aids tracking and alignment of the primary mirror segments. The first phase of HET instrumentation included three facility instruments: the Low Resolution Spectrograph (LRS), the Medium Resolution Spectrograph (MRS), and High Resolution Spectrograph (HRS). The current status of these instruments is briefly described. A major upgrade of HET is in progress that will increase the field of view to 22 arcminutes diameter, replacing the corrector, tracker and prime focus instrument package. This wide field upgrade will feed a revolutionary new integral field spectrograph called VIRUS, in support of the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). VIRUS is a facility instrument that consists of 150 or more copies of a simple unit integral field spectrograph. In total VIRUS will observe 34,000 spatial elements simultaneously, and will open up wide-area surveys of the emission-line universe for the first time. We describe the HET wide field upgrade and the development of VIRUS, including results from testing the prototype of the VIRUS unit spectrograph.

Select this Article		Commissioning of the Southern African Large Telescopes (SALT) first-generation instruments D. A. H. Buckley, S. I. Barnes, E. B. Burgh, S. Crawford, P. L. Cottrell, A. Kniazev, K. H. Nordsieck, D. O'Donoghue, N. Rangwala, R. Zánmar Sánchez, R. M. Sharples, A. I. Sheinis, P. Väisänen, and T. B. Williams Proc. SPIE 7014, 701407 (2008); http://dx.doi.org/10.1117/12.789438 \| Cited 2 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Southern African Large Telescope is nearing the end of its commissioning phase and scientific performance verification programmes began in 2006 with two of its First Generation UV-visible instruments, the imaging camera, SALTICAM, and the multi-mode Robert Stobie Spectrograph (RSS). Both instruments are seeing limited and designed to operate in the UV-visible region (320 - 900 nm). This paper reviews the innovative aspects of the designs of these instruments and discusses the commissioning experience to date, illustrated by some initial scientific commissioning results. These include long-slit and multi-object spectroscopy, spectropolarimetry, Fabry-Perot imaging spectroscopy and high-speed photometry. Early spectroscopic commissioning results uncovered a serious underperformance in the throughput of RSS, particularly at wavelengths < 400nm. We discuss the lengthy diagnosis and eventual removal of this problem, which was traced to a material incompatibility issue involving index-matching optical coupling fluid. Finally, we briefly discuss the present status of the third and final First Generation instrument, a vacuum enclosed fibre-fed high resolution, dual beam, white pupil echelle spectrograph, SALT HRS, currently under construction.

Select this Article		The GTC facility instruments: a status review J. M. Rodriguez Espinosa and Pedro Alvarez Martin Proc. SPIE 7014, 701408 (2008); http://dx.doi.org/10.1117/12.787790 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Gran Telescopio Canarias (GTC) 10.4m telescope received its First Light on July 13, 2007. At present the GTC is undergoing commissioning tests. Night time observations are being carried out routinely from Monday through to Thursday every week. The GTC will begin science observation by the end of the year, and will be offered to the community in September 2008 for the semester starting in March 09. The two first generation science instruments are getting ready to be mounted on the telescope. In this talk I will go through the main features of the first generation science instruments and describe their status of completion. I will also devote some time to the second-generation instruments that are currently at various states of advancement. These include EMIR, a wide field multi-object K band cryogenic spectrograph, and FRIDA, which is a near IR Adaptive Optics fed integral field spectrograph. Finally, I will describe a set of smaller instruments that will complement and indeed extend the observing capabilities of the GTC soon after the start of science operation.

Select this Article		An overview of instrumentation for the Large Binocular Telescope R. Mark Wagner Proc. SPIE 7014, 701409 (2008); http://dx.doi.org/10.1117/12.789999 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract An overview of instrumentation for the Large Binocular Telescope is presented. Optical instrumentation includes the Large Binocular Camera (LBC), a pair of wide-field (27' × 27') mosaic CCD imagers at the prime focus, and the Multi-Object Double Spectrograph (MODS), a pair of dual-beam blue-red optimized long-slit spectrographs mounted at the straight-through F/15 Gregorian focus incorporating multiple slit masks for multi-object spectroscopy over a 6 field and spectral resolutions of up to 8000. Infrared instrumentation includes the LBT Near-IR Spectroscopic Utility with Camera and Integral Field Unit for Extragalactic Research (LUCIFER), a modular near-infrared (0.9-2.5 μm) imager and spectrograph pair mounted at a bent interior focal station and designed for seeing-limited (FOV: 4' × 4') imaging, long-slit spectroscopy, and multi-object spectroscopy utilizing cooled slit masks and diffraction limited (FOV: 0.5' × 0.5') imaging and long-slit spectroscopy. Strategic instruments under development for the remaining two combined focal stations include an interferometric cryogenic beam combiner with near-infrared and thermal-infrared instruments for Fizeau imaging and nulling interferometry (LBTI) and an optical bench near-infrared beam combiner utilizing multi-conjugate adaptive optics for high angular resolution and sensitivity (LINC-NIRVANA). In addition, a fiber-fed bench spectrograph (PEPSI) capable of ultra high resolution spectroscopy and spectropolarimetry (R = 40,000-300,000) will be available as a principal investigator instrument. The availability of all these instruments mounted simultaneously on the LBT permits unique science, flexible scheduling, and improved operational support.

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Instrumentation at Major Observatories II

Select this Article		Instrumentation at the Magellan Telescopes 2008 David J. Osip, David Floyd, and Ricardo Covarrubias Proc. SPIE 7014, 70140A (2008); http://dx.doi.org/10.1117/12.790011 \| Cited 1 time Online Publication Date: Jul 24, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Carnegie Institution operates the twin 6.5m Magellan Telescopes on behalf of the Magellan consortium (Carnegie Institution of Washington, Harvard University, the University of Arizona, Massachusetts Institute of Technology, and the University of Michigan). The two telescopes have been in routine operations at the Las Campanas Observatory since 2001 and 2002 respectively. We currently operate with a suite of instruments available at 6 active ports during regular night-time science operations. Here, we briefly describe the capabilities, operation, and performance of the suite of commissioned instruments including MagIC, PANIC, MIKE, MIKE-Fibers, LDSS3, IMACS, and MagE. Beyond the instruments that are presently installed on site, we will also introduce the large number of instruments that are in advanced stages of construction by teams throughout our consortium (FIRE, Four-Star, MegaCam, MMIRS, PFS, PISCO, MIRAC4).

Select this Article		Comprehensive review of the converted MMT's instrument suite M. Hastie and B. McLeod Proc. SPIE 7014, 70140B (2008); http://dx.doi.org/10.1117/12.790233 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The converted 6.5m MMT Observatory has a powerful suite of new instrumentation accumulated over the last eight years. Pre-conversion instruments still in use at the f/9 Cassegrain focus are the facility Red and Blue Channel spectrographs (R = 240 - 6600) and the visiting spectropolarimeter (SPOL). Instruments using the f/5 spectroscopic configuration are the bench mounted 300-fiber spectrographs Hectospec (R=1000) and Hectochelle (R=30,000), and the single slit, cross-dispersed spectrograph MAESTRO (R=28,000 - 93,000). The f/5 imaging configuration offers Megacam, a 24' x 24' CCD mosaic camera and SWIRC, a YJH NIR imager. The MMT's pioneering f/15 adaptive secondary mirror enables high-resolution imaging and spectroscopy in the infrared with the ARIES, CLIO, PISCES and BLINC/MIRAC instruments. The AO system will shortly be significantly enhanced with the addition of a Rayleigh laser guide star system which is currently being commissioned. Upcoming instrumentation will include slit mask spectrographs in the infrared (MMIRS) and optical (BINOSPEC). This review paper presents all the available instruments capabilities and demonstrates how the observatory has become highly efficient at managing multiple secondary mirrors and a large instrument suite.

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Optical Imaging

Select this Article		The LSST camera overview: design and performance Kirk Gilmore, Steven Kahn, Martin Nordby, Paul O'Connor, John Oliver, Veljko Radeka, Terry Schalk, Rafe Schindler, and Rick Van Berg Proc. SPIE 7014, 70140C (2008); http://dx.doi.org/10.1117/12.789947 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The LSST camera is a wide-field optical (0.35-1μm) imager designed to provide a 3.5 degree FOV with 0.2 arcsecond/pixel sampling. The detector format will be a circular mosaic providing approximately 3.2 Gigapixels per image. The camera includes a filter mechanism and shuttering capability. It is positioned in the middle of the telescope where cross-sectional area is constrained by optical vignetting and where heat dissipation must be controlled to limit thermal gradients in the optical beam. The fast f/1.2 beam will require tight tolerances on the focal plane mechanical assembly. The focal plane array operates at a temperature of approximately -100°C to achieve desired detector performance. The focal plane array is contained within a cryostat which incorporates detector front-end electronics and thermal control. The cryostat lens serves as an entrance window and vacuum seal for the cryostat. Similarly, the camera body lens serves as an entrance window and gas seal for the camera housing, which is filled with a suitable gas to provide the operating environment for the shutter and filter change mechanisms. The filter carousel accommodates 5 filters, each 75 cm in diameter, for rapid exchange without external intervention.

Select this Article		The Pan-STARRS Gigapixel Camera #1 and STARGRASP controller results and performance P. Onaka, J. L. Tonry, S. Isani, A. Lee, R. Uyeshiro, C. Rae, L. Robertson, and G. Ching Proc. SPIE 7014, 70140D (2008); http://dx.doi.org/10.1117/12.788093 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Pan-STARRS project has completed its first 1.4 gigapixel mosaic focal plane CCD camera, Gigapixel Camera #1 (GPC1). The mosaic focal plane of 60 densely packed 4k×4k MITLL CCD Orthogonal Transfer Arrays (OTAs) constitutes the World's largest CCD camera. The camera represents an extremely cost and time efficient effort with a less than 18 month production and integration phase and an approximate cost of $4 million USD (excluding NRE). The controller electronics named STARGRASP was developed to handle the 480 outputs at near 1Mpixel/sec rates with Gigabit Ethernet interfaces and can be scaled to even larger focal planes. Sophisticated functionality was developed for guide readout and on-detector tip-tilt image compensation with selectable region logic for standby or active operation, high output count, close four side buttable packaging and deep depletion construction. We will discuss the performance achieved, on-sky results, design, tools developed, shortcomings and future plans.

Select this Article		The Dark Energy Camera (DECam) D. L. DePoy, T. Abbott, J. Annis, M. Antonik, M. Barceló, R. Bernstein, B. Bigelow, D. Brooks, E. Buckley-Geer, J. Campa, L. Cardiel, F. Castander, J. Castilla, H. Cease, S. Chappa, et al. Proc. SPIE 7014, 70140E (2008); http://dx.doi.org/10.1117/12.789466 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the Dark Energy Camera (DECam), which will be the primary instrument used in the Dark Energy Survey. DECam will be a 3 sq. deg. mosaic camera mounted at the prime focus of the Blanco 4m telescope at the Cerro-Tololo International Observatory (CTIO). DECam includes a large mosaic CCD focal plane, a five element optical corrector, five filters (g,r,i,z,Y), and the associated infrastructure for operation in the prime focus cage. The focal plane consists of 62 2K x 4K CCD modules (0.27"/pixel) arranged in a hexagon inscribed within the roughly 2.2 degree diameter field of view. The CCDs will be 250 micron thick fully-depleted CCDs that have been developed at the Lawrence Berkeley National Laboratory (LBNL). Production of the CCDs and fabrication of the optics, mechanical structure, mechanisms, and control system for DECam are underway; delivery of the instrument to CTIO is scheduled for 2010.

Select this Article		First light of UT 15-band dichroic-mirror camera Mamoru Doi, Junji Hayano, Hiroyuki Utsunomiya, Yutaka Ihara, Kouichi Tokita, Shigeyuki Sako, Sadanori Okamura, Naohiro Takanashi, Tomoki Morokuma, Hisanori Furusawa, Hidehiko Nakaya, Yutaka Komiyama, Masafumi Yagi, Norio Okada, Akira Arai, et al. Proc. SPIE 7014, 70140F (2008); http://dx.doi.org/10.1117/12.788554 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract A dichroic mirror/filter can divide light into two different wavelength bands by the principle of interference. We proposed to use more than a dozen of these mirrors, and make a simultaneous imager in many color bands. This also enables us to make a powerful spectrograph which uses many CCDs. We here report the first light of UT 15-band Dichroic-Mirror Camera. We successfully obtained the first light at the Cassegrain focus of the 1.5-m Kanata telescope in May 2007. We also carried out the second observing run in March 2008. Our instrument covers a wide wavelength range (390-930nm), and the field of view is about 4.5 arcmin in diameter with 0.27arcsec/pixel. Image quality was limited by seeing (~1.2 arcsec at best). We describe basic design, characteristics, and performance of our instrument as well as early observational results. Future prospect of dichroic mirrors instruments will also be briefly discussed.

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Optical Spectroscopy

Select this Article		WIYN bench upgrade: a revitalized spectrograph M. Bershady, S. Barden, P.-A. Blanche, D. Blanco, C. Corson, S. Crawford, J. Glaspey, S. Habraken, G. Jacoby, J. Keyes, P. Knezek, P. Lemaire, M. Liang, E. McDougall, G. Poczulp, et al. Proc. SPIE 7014, 70140H (2008); http://dx.doi.org/10.1117/12.789112 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the redesign and upgrade of the versatile fiber-fed Bench Spectrograph on the WIYN 3.5m telescope. The spectrograph is fed by either the Hydra multi-object positioner or integral-field units (IFUs) at two other ports, and can be configured with an adjustable camera-collimator angle to use low-order and echelle gratings. The upgrade, including a new collimator, charge-coupled device (CCD) and modern controller, and volume-phase holographic gratings (VPHG), has high performance-to-cost ratio by combining new technology with a system reconfiguration that optimizes throughput while utilizing as much of the existing instrument as possible. A faster, all-refractive collimator enhances throughput by 60%, nearly eliminates the slit-function due to vignetting, and improves image quality to maintain instrumental resolution. Two VPH gratings deliver twice the diffraction efficiency of existing surface-relief gratings: A 740 l/mm grating (float-glass and post-polished) used in 1st and 2nd-order, and a large 3300 l/mm grating (spectral resolution comparable to the R2 echelle). The combination of collimator, high-quantum efficiency (QE) CCD, and VPH gratings yields throughput gain-factors of up to 3.5.

Select this Article		A spatial heterodyne spectrometer for diffuse H-α spectroscopy Andrew I. Sheinis, Ed Mierkiewicz, Fred Roesler, John Harlander, and Andrew Bodkin Proc. SPIE 7014, 70140I (2008); http://dx.doi.org/10.1117/12.788470 \| Cited 2 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The University of Wisconsin Astronomy Department and the Space Astronomy Lab at UW are designing an SHS spectrometer for the WIYN 3.5-meter telescope on Kitt Peak and the SALT 10-meter telescope in South Africa. The new device will be mated to the Sparsepak, (Bershady et al, 2004, 2005) and/or the Hydra fiber array at WIYN, and fed by either the prime focus image at SALT or the High Resolution Spectrograph fiber-feed at SALT. The spectrograph will produce spectra at a reciprocal dispersion, R = 25,000 in 20 orders, each order covering an average wavelength band 250 km/s wide, for a total wavelength range of 5000 km/s. Spectra from approximately 82 fibers will be resolved. Once the system is proven at WIYN, and because the aperture size for this spectrometer does not scale with telescope size, we will be able to test this same prototype at the SALT 10-meter telescope. This will be the first application of this technique to large aperture astronomical observations.

Select this Article		The SOPHIE spectrograph: design and technical key-points for high throughput and high stability S. Perruchot, D. Kohler, F. Bouchy, Y. Richaud, P. Richaud, G. Moreaux, M. Merzougui, R. Sottile, L. Hill, G. Knispel, X. Regal, J.-P. Meunier, S. Ilovaisky, H. Le Coroller, D. Gillet, et al. Proc. SPIE 7014, 70140J (2008); http://dx.doi.org/10.1117/12.787379 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract SOPHIE is a new fiber-fed echelle spectrograph in operation since October 2006 at the 1.93-m telescope of Observatoire de Haute-Provence. Benefiting from experience acquired on HARPS (3.6-m ESO), SOPHIE was designed to obtain accurate radial velocities (~3 m/s over several months) with much higher optical throughput than ELODIE (by a factor of 10). These enhanced capabilities have actually been achieved and have proved invaluable in asteroseismology and exoplanetology. We present here the optical concept, a double-pass Schmidt echelle spectrograph associated with a high efficiency coupling fiber system, and including simultaneous wavelength calibration. Stability of the projected spectrum has been obtained by the encapsulation of the dispersive components in a constant pressure tank. The main characteristics of the instrument are described. We also give some technical details used in reaching this high level of performance.

Select this Article		The optical design of the Southern African large telescope high resolution spectrograph: SALT HRS S. I. Barnes, P. L. Cottrell, M. D. Albrow, N. Frost, G. Graham, G. Kershaw, R. Ritchie, D. Jones, R. Sharples, D. Bramall, J. Schmoll, P. Luke, P. Clark, L. Tyas, D. A. H. Buckley, et al. Proc. SPIE 7014, 70140K (2008); http://dx.doi.org/10.1117/12.788219 \| Cited 4 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract SALT HRS is a fiber-fed cross-dispersed echelle spectrograph designed for high resolution and high efficiency seeing-limited spectroscopy on the Southern African Large Telescope. The spectrograph, which has a dual channel white pupil design, uses a single R4 echelle grating, a dichroic beam-splitter, and volume phase holographic gratings as cross-dispersers. The echelle grating has 41.6 grooves/mm and is illuminated with a 200mm diameter beam. This allows R = 16,000 with a 2.2" fiber and complete wavelength coverage from 370 nm to 890 nm. Resolving powers of R ≈ 37,000 and 67,000 are obtained using image slicers. The dichroic beam-splitter is used to split the wavelength coverage between two fully dioptric cameras. The white pupil transfer optics are used to demagnify the pupil to 111mm which ensures that the camera dimensions are kept reasonable whilst also allowing the efficient use of VPH gratings. The spectrograph optics are enclosed inside a vacuum tank to ensure immunity to atmospheric pressure and temperature changes. The entire spectrograph is mechanically and thermally insulated. Construction of SALT HRS began at Durham University's Centre for Advanced Instrumentation in August 2007 and is expected to be complete in 2009. The spectrograph optical design is largely based on work completed at the University of Canterbury's Department of Physics and Astronomy.

Select this Article		SixPak: a wide-field IFU for the William Herschel Telescope Lars B. Venema, Ton Schoenmaker, Marc Verheijen, Scott Trager, René Rutten, Matthew Bershady, Søren Larsen, Reynier Peletier, and Marco Spaans Proc. SPIE 7014, 70140L (2008); http://dx.doi.org/10.1117/12.789130 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We intend to construct SixPak, a wide-field fibre-based IFU for the 4.2-meter William Herschel Telescope on La Palma. The fibre bundle will consist of 238 fibres, each 3.0 arcsec in diameter, piping light from the Nasmyth focal plane of the WHT to the existing WYFFOS bench spectrograph. A total of 217 fibres will be densely packed to span a hexagonal field of view of 64 × 55 arcsec. The remaining 21 fibres will collect light from the sky background. SixPak is optimized for 2-dimensional spectroscopy at intermediate resolutions of extended objects of low surface brightness. At Nasmyth focus, a focal reducer matches the f-ratio of the telescope (f/11) to the "optimal" f-ratio of the fibres (f/3) to reduce the losses due to focal ratio degradation in the fibres. Microlenses convert the output f-ratio of the fibres to the f-ratio of the WYFFOS collimator (f/8.2). By means of an exchangeable slit at the pupils of the microlenses, a spectral resolution of R = 10,000 can be achieved. The intention is that SixPak will be open for general use in order to allow easy access to the broadest possible astronomical community.

Select this Article		New design approaches for a very high resolution spectrograph for the combined focus of the VLT Paolo Spanò, Bernard Delabre, Hans Dekker, and Gerardo Avila Proc. SPIE 7014, 70140M (2008); http://dx.doi.org/10.1117/12.789283 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract To achieve very-high spectral resolutions (R>100,000) with large telescopes (D>8m) new optical solutions have been investigated in the context of the ESPRESSO project for the VLT, starting from the initial design of CODEX for the E-ELT. ESPRESSO is a high-efficiency, high-stability, high-resolution visible spectrograph for the combined Coude focus of the VLT. Among these new solutions, we can mention: free-form optics, used to design an all-mirror anamorphic pupil slicer, large mosaic echelle grating, slanted VPH gratings, super-corrected atmospheric dispersion corrector. All these solutions have been usefully applied to design the spectrograph for ESPRESSO, and its Coude relay system.

Select this Article		PEPSI: the Potsdam Echelle Polarimetric and Spectroscopic Instrument for the LBT K. G. Strassmeier, M. Woche, I. Ilyin, E. Popow, S.-M. Bauer, F. Dionies, T. Fechner, M. Weber, A. Hofmann, J. Storm, R. Materne, W. Bittner, J. Bartus, T. Granzer, C. Denker, et al. Proc. SPIE 7014, 70140N (2008); http://dx.doi.org/10.1117/12.787376 \| Cited 3 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the status of PEPSI, the bench-mounted fibre-fed and stabilized "Potsdam Echelle Polarimetric and Spectroscopic Instrument" for the 2×8.4m Large Binocular Telescope in southern Arizona. PEPSI is under construction at AIP and is scheduled for first light in 2009/10. Its ultra-high-resolution mode will deliver an unprecedented spectral resolution of approximately R=310,000 at high efficiency throughout the entire optical/red wavelength range 390-1050nm without the need for adaptive optics. Besides its polarimetric Stokes IQUV mode, the capability to cover the entire optical range in three exposures at resolutions of 40,000, 130,000 and 310,000 will surpass all existing facilities in terms of light-gathering-power times spectral-coverage product. A solar feed will make use of the spectrograph also during day time. As such, we hope that PEPSI will be the most powerful spectrometer of its kind for the years to come.

Select this Article		The upgrade of HARPS to a full-Stokes high-resolution spectropolarimeter Frans Snik, Sandra Jeffers, Christoph Keller, Nikolai Piskunov, Oleg Kochukhov, Jeff Valenti, and Christopher Johns-Krull Proc. SPIE 7014, 70140O (2008); http://dx.doi.org/10.1117/12.787393 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design of a compact module that converts the HARPS instrument at the 3.6-m telescope at La Silla to a full-Stokes high-resolution spectropolarimeter. The polarimeter will replace the obsolete Iodine cell inside the HARPS Cassegrain adapter. Utilizing the two fibers going into the spectrograph, two dual-beam systems can be positioned in the beam: one with a rotating superachromatic quarter-wave plate for circular polarimetry and one with a rotating superachromatic half-wave plate for linear polarimetry. A large polarimetric precision is ensured by the beam-exchange technique and a minimal amount of instrumental polarization. The polarimeter, in combination with the ultra-precise HARPS spectrograph, enables unprecedented observations of stellar magnetic fields and circumstellar material without compromising the successful planet-finding program.

Select this Article		The spectrograph ESOPO: scientific goals, high-level requirements, and introduction to the design J. Echevarría, A. Farah, R. Costero, J. González, G. Avila, M. Arroyo, F. Cobos, E. Colorado, A. Córdova, O. Chapa, B. García, F. Garfias, F. Granados, G. Guisa, E. Luna, et al. Proc. SPIE 7014, 70140P (2008); http://dx.doi.org/10.1117/12.790217 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In this paper we present the Medium Resolution Spectrograph ESOPO, an instrument designed and built for the 2.1m Telescope at the Observatorio AstronɃmico Nacional at San Pedro Mȥrtir. We discuss the Scientific Goals and the High Level Requirements necessary to translate these goals to optical, mechanical and control specifications. We make an introduction to its conceptual dual-arm design. The optical design is based on a non-classical configuration. The gratings are illuminated in a conical mode working in a quasi Littrow configuration which has the advantage of optimizing the efficiency and the pupil area on the grating. We show here the results of an experimental evaluation of the concept. The optical design, mechanical structure, slit-mask and acquisition system, control systems, and a study of thermal compensators, are discussed briefly, references to more extended contributions in these proceedings are made. The management schematics of the project are briefly discussed.

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Infrared Cameras and Spectrometers

Select this Article		Performance of HAWK-I: the new high acuity wide-field K-band imager M. Kissler-Patig, N. Ageorges, C. Alves de Oliveira, L. R. Bedin, E. Bendek, M. Casali, R. Dorn, R. Esteves, G. Finger, D. Gojak, Y. Jung, M. Kiekebusch, A. Moorwood, J.-L. Lizon, M. Petr-Gotzens, et al. Proc. SPIE 7014, 70140Q (2008); http://dx.doi.org/10.1117/12.787009 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract HAWK-I is the newly commissioned High Acuity Wide-field K-band Imager at the ESO Very Large Telescope. It is a 0.9-2.5 micron imager with a field of view of 7.5×7.5 arcmin sampled at 106 mas with four Hawaii2RG detectors. It has a full reflective design that was optimised for image quality and throughput.We present an overview of its performance as measured during the commissioning and first science runs. In particular, we describe a detector read-out mode that allows us to increase the useful dynamic range of the detector, and a distortion calibration resulting in <5mas relative astrometry across the field.

Select this Article		Day-one science with CanariCam: the Gran Telescopio Canarias multi-mode mid-infrared camera Charles M. Telesco, Christopher Packham, Christ Ftaclas, James H. Hough, Margaret M. Moerchen, Kevin T. Hanna, Jeffrey A. Julian, Frank Varosi, Roger E. Julian, Greg Bennett, Charles Murphey, Francisco Reyes, and Craig Warner Proc. SPIE 7014, 70140R (2008); http://dx.doi.org/10.1117/12.787697 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract CanariCam is the facility multi-mode mid-IR camera developed by the University of Florida for the 10-meter Gran Telescopio Canarias (GTC) on La Palma. CanariCam has four science modes that provide the GTC community with an especially powerful research tool for imaging, grating spectroscopy, coronagraphy, and dual-beam polarimetry. Instrument commissioning in the laboratory at the University of Florida indicates that all modes perform as required, and the next step is on-telescope commissioning. After commenting on the instrument status, we will review key features of each of these science modes, with emphasis on illustrating each mode with science examples that put the system performance, particularly the anticipated sensitivity, into perspective.

Select this Article		FMOS: the fiber multiple-object spectrograph: Part VI. Onboard performances and results of the engineering observations Fumihide Iwamuro, Toshinori Maihara, Masayuki Akiyama, Masahiko Kimura, Naoyuki Tamura, Naruhisa Takato, Philip Tait, Kouji Ohta, Shigeru Eto, Yuuki Moritani, Gavin B. Dalton, Ian J. Lewis, Hanshin Lee, Ian A. J. Tosh, Tim R. Froud, et al. Proc. SPIE 7014, 70140T (2008); http://dx.doi.org/10.1117/12.787746 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FMOS: the Fiber Multiple-Object Spectrograph is the next common-use instrument of the Subaru Telescope, having a capability of 400 targets multiplicity in the near-infrared 0.9-1.8μm wavelength range with a field coverage of 30' diameter. FMOS consists of three units: 1) the prime focus unit including the corrector lenses, the Echidna fiber positioner, and the instrument-bay to adjust the instrument focus and shift the axis of the corrector lens system, 2) the fiber bundle unit equipping two fiber slits on one end and a fiber connector box with the back-illumination mechanism on the other end on the bundle, 3) the two infrared spectrographs (IRS1 and IRS2) to obtain 2×200 spectra simultaneously. After all the components were installed in the telescope at the end of 2007, the total performance was checked through various tests and engineering observations. We report the results of these tests and demonstrate the performance of FMOS.

Select this Article		FIRE: a near-infrared cross-dispersed echellette spectrometer for the Magellan telescopes Robert A. Simcoe, Adam J. Burgasser, Rebecca A. Bernstein, Bruce C. Bigelow, Jason Fishner, William J. Forrest, Craig McMurtry, Judith L. Pipher, Paul L. Schechter, and Matthew Smith Proc. SPIE 7014, 70140U (2008); http://dx.doi.org/10.1117/12.790414 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FIRE (the Folded-port InfraRed Echellette) is a prism cross-dispersed infrared spectrometer, designed to deliver singleobject R=6000 spectra over the 0.8-2.5 micron range, simultaneously. It will be installed at one of the auxiliary Nasmyth foci of the Magellan 6.5-meter telescopes. FIRE employs a network of ZnSe and Infrasil prisms, coupled with an R1 reflection grating, to image 21 diffraction orders onto a 2048 × 2048, HAWAII-2RG focal plane array. Optionally, a user-controlled turret may be rotated to replace the reflection grating with a mirror, resulting in a singleorder, longslit spectrum with R ~ 1000. A separate, cold infrared sensor will be used for object acquisition and guiding. Both detectors will be controlled by cryogenically mounted SIDECAR ASICs. The availability of low-noise detectors motivates our choice of spectral resolution, which was expressly optimized for Magellan by balancing the scientific demand for increased R with practical limits on exposure times (taking into account statistics on seeing conditions). This contribution describes that analysis, as well as FIRE's optical and opto-mechanical design, and the design and implementation of cryogenic mechanisms. Finally, we will discuss our data-flow model, and outline strategies we are putting in place to facilitate data reduction and analysis.

Select this Article		FLAMINGOS-2: the facility near-infrared wide-field imager and multi-object spectrograph for Gemini Stephen Eikenberry, Richard Elston, S. Nicholas Raines, Jeff Julian, Kevin Hanna, Craig Warner, Roger Julian, Reba Bandyopadhyay, J. Greg Bennett, Aaron Bessoff, Matt Branch, Richard Corley, Curtis Dewitt, John-David Eriksen, Skip Frommeyer, et al. Proc. SPIE 7014, 70140V (2008); http://dx.doi.org/10.1117/12.788326 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We report on the design and status of the FLAMINGOS-2 instrument - a fully-cryogenic facility near-infrared imager and multi-object spectrograph for the Gemini 8-meter telescopes. FLAMINGOS-2 has a refractive all-spherical optical system providing 0.18-arcsecond pixels and a 6.2-arcminute circular field-of-view on a 2048×2048-pixel HAWAII-2 0.9-2.4 μm detector array. A slit/decker wheel mechanism allows the selection of up to 9 multi-object laser-machined plates or 3 long slits for spectroscopy over a 6×2-arcminute field of view, and selectable grisms provide resolutions from ~1300 to ~3000 over the entire spectrograph bandpass. FLAMINGOS-2 is also compatible with the Gemini Multi- Conjugate Adaptive Optics system, providing multi-object spectroscopic capabilities over a 3×1-arcminute field with high spatial resolution (0.09-arcsec/pixel). We review the designs of optical, mechanical, electronics, software, and On- Instrument WaveFront Sensor subsystems. We also present the current status of the project and future plans, including on-sky delivery planned for late 2008.

Select this Article		CRIRES: commissioning and first science results Hans Ulrich Käufl, Paola Amico, Pascal Ballester, Eduardo A. Bendek Selman, Paul Bristow, Mark Casali, Bernard Delabre, Danuta Dobrzycka, Reinhold J. Dorn, Raul Esteves, Gert Finger, Gordon Gillet, Domingo Gojak, Michael Hilker, Paul Jolley, et al. Proc. SPIE 7014, 70140W (2008); http://dx.doi.org/10.1117/12.787259 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract CRIRES is a cryogenic, pre-dispersed, infrared Echelle spectrograph designed to provide a nominal resolving power ν/Δν of 10⁵ between 1000 and 5000 nm for a nominal slit width of 0.2". The CRIRES installation at the Nasmyth focus A of the 8-m VLT UT1 (Antu) marks the completion of the original instrumentation plan for the VLT. A curvature sensing adaptive optics system feed is used to minimize slit losses and to provide 0.2" spatial resolution along the slit. A mosaic of four Aladdin InSb-arrays packaged on custom-fabricated ceramic boards has been developed. It provides for an effective 4096 × 512 pixel focal plane array to maximize the free spectral range covered in each exposure. Insertion of gas cells is possible in order to measure radial velocities with high precision. Measurement of circular and linear polarization in Zeeman sensitive lines for magnetic Doppler imaging is foreseen but not yet fully implemented. A cryogenic Wollaston prism on a kinematic mount is already incorporated. The retarder devices will be located close to the Unit Telescope focal plane. Here we briefly recall the major design features of CRIRES and describe the commissioning of the instrument including a report of extensive testing and a preview of astronomical results.

Select this Article		The performance of TripleSpec at Palomar Terry L. Herter, Charles P. Henderson, John C. Wilson, Keith Y. Matthews, Gustavo Rahmer, Marco Bonati, Philip S. Muirhead, Joseph D. Adams, James P. Lloyd, Michael F. Skrutskie, Dae-Sik Moon, Stephen C. Parshley, Matthew J. Nelson, Frantz Martinache, and George E. Gull Proc. SPIE 7014, 70140X (2008); http://dx.doi.org/10.1117/12.789660 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We report the performance of Triplespec from commissioning observations on the 200-inch Hale Telescope at Palomar Observatory. Triplespec is one of a set of three near-infrared, cross-dispersed spectrographs covering wavelengths from 1 - 2.4 microns simultaneously at a resolution of ~2700. At Palomar, Triplespec uses a 1×30 arcsecond slit. Triplespec will be used for a variety of scientific observations, including moderate to high redshift galaxies, star formation, and low mass stars and brown dwarfs. When used in conjunction with an externally dispersed interferometer, Triplespec will also detect and characterize extrasolar planets.

Select this Article		Precision radial velocity spectrograph Hugh R. A. Jones, John Rayner, Larry Ramsey, David Henry, Bill Dent, David Montgomery, Andy Vick, Derek Ives, Ian Egan, David Lunney, Phil Rees II, Adrian Webster, Chris Tinney, and Mike Liu Proc. SPIE 7014, 70140Y (2008); http://dx.doi.org/10.1117/12.789807 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present a conceptual design for a Precision Radial Velocity Spectrograph (PRVS) for the Gemini telescope. PRVS is a fibre fed high resolving power (R~70,000 at 2.5 pixel sampling) cryogenic echelle spectrograph operating in the near infrared (0.95 - 1.8 microns) and is designed to provide 1 m/s radial velocity measurements. We identify the various error sources to overcome in order to the required stability. We have constructed models simulating likely candidates and demonstrated the ability to recover exoplanetary RV signals in the infrared. PRVS should achieve a total RV error of around 1 m/s on a typical M6V star. We use these results as an input to a simulated 5-year survey of nearby M stars. Based on a scaling of optical results, such a survey has the sensitivity to detect several terrestrial mass planets in the habitable zone around nearby stars. PRVS will thus test theoretical planet formation models, which predict an abundance of terrestrial-mass planets around low-mass stars.We have conducted limited experiments with a brass-board instrument on the Sun in the infrared to explore real-world issues achieving better than 10 m/s precision in single 10 s exposures and better than 5 m/s when integrated across a minute of observing.

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Airborne Instruments

Select this Article		Verification of the optical system performance of FIFI LS: the field-imaging far-infrared line spectrometer for SOFIA Mario Schweitzer, Albrecht Poglitsch, Walfried Raab, Randolf Klein, Rainer Hönle, Norbert Geis, Reinhard Genzel, Leslie W. Looney, M. Hamidouche, and Thomas K. Henning Proc. SPIE 7014, 70140Z (2008); http://dx.doi.org/10.1117/12.787383 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FIFI-LS is a Field-Imaging Line Spectrometer designed for the SOFIA airborne observatory. The instrument will operate in the far infrared (FIR) wavelength range from 42 to 210 μm. Two spectrometers operating between 42-110 μm and 110-210 μm allow simultaneous and independent diffraction limited 3D imaging over a field of view of 6" × 6" and 12" × 12" respectively. We have developed a telescope simulator to test the imaging and spectral performance of FIFI-LS in the FIR. Here, we present the telescope simulator as well as the performance verification of FIFI-LS using the simulator. Finally we compare the measurements with the theoretical expected performance of FIFI-LS.

Select this Article		GREAT: a first light instrument for SOFIA S. Heyminck, R. Güsten, P. Hartogh, H.-W. Hübers, J. Stutzki, and U. U. Graf Proc. SPIE 7014, 701410 (2008); http://dx.doi.org/10.1117/12.788273 \| Cited 2 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract GREAT (German REceiver for Astronomy at Terahertz frequencies) has been selected as first-light instrument for the early science flights of SOFIA, scheduled for early 2009. In its first-light configuration GREAT will allow observations in two out of three FIR bands: two low frequency channels 1.25-1.5 THz and 1.82-1.92 THz for observations of, e.g., highly excited CO and of ionized carbon, and a 2.7 THz channel focusing on the ground-state transition of deuterated molecular hydrogen HD. A forth channel, centered on the 4.7 THz transition of atomic oxygen will become available later. The observatory schedule asks for delivery of the instrument in early 2009. At the time of the conference system level assembly, integration, and verification (AIV) is ongoing, and we report on the performance of the integrated system. Shipment to NASA/DAOF (Dryden aircraft operations facility) in Palmdale/California for aircraft integration is currently planned for mid December 2008.

Select this Article		Ground-based commissioning of FLITECAM Erin C. Smith and Ian S. McLean Proc. SPIE 7014, 701411 (2008); http://dx.doi.org/10.1117/12.788693 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FLITECAM is a 1-5 micron spectrometer and camera developed at UCLA for NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA). On SOFIA, FLITECAM will take advantage of lower backgrounds from 3-5 microns and will provide access to spectral regions completely or partially absorbed by water vapor at even the best ground-based sites. FLITECAM employs large cryogenic optics and an ALADDIN III 1024 × 1024 InSb detector to inscribe an 8 arcminute field of view with 0.48 arcsec/pixel spatial resolution. The optical components are cooled with liquid nitrogen and a liquid helium reservoir is used to establish an operational temperature of 30 K for the InSb array. FLITECAM has two primary observing modes, imaging and spectroscopy. A pupil-viewing mode, for examination of the primary mirror surface, and a high-speed snapshot mode for occultation observations are also provided. Ground-based commissioning of the instrument using the Shane 3-meter telescope at UCO/Lick Observatory has been completed successfully. In addition to broad-band filters, the imaging mode accommodates several narrow-band filters. A data reduction pipeline processes dithered image sets in real-time during the flight. The grism spectroscopy mode employs three direct-ruled KRS-5 grisms and fixed slits of either 1" × 60" or 2 × 60" to yield resolving powers (FWHM) of R~1700 and 900 respectively. Observations are scripted using AORs (Astronomical Observation Requests) in both modes. A pilot survey of 3.3 micron emission in planetary nebulae performed with FLITECAM at UCO/Lick Observatory demonstrates the potential of the grism mode.

Select this Article		Improved sensitivity of the SOFIA target acquisition and tracking cameras and a high speed diagnostics camera for telescope movements in flight Jürgen Wolf, Hans-Peter Röser, Sascha Tietz, Manuel Wiedemann, Enrico Pfüller, and Dietmar Lilienthal Proc. SPIE 7014, 701412 (2008); http://dx.doi.org/10.1117/12.790089 \| Cited 2 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The telescope of the Stratospheric Observatory for Infrared Astronomy (SOFIA) uses three CCD based visible light cameras for target acquisition and tracking. All three cameras use the TH7888A CCD chips which are quite suitable in terms of their geometry and readout speed. However, their quantum efficiency and dark current are not comparable to newer high-sensitivity CCD chips now widely used in astronomy. The Deutsche SOFIA Institute (DSI) under contract of the German Aerospace Center (DLR) has therefore initiated an upgrade project of the cameras with back-illuminated, high-sensitivity and low dark current CCD chips, e2v 47-20. The expected improvements in sensitivity range between 1.2 and 2.5 stellar magnitudes for the three cameras. In addition, DSI and DLR plan to provide a high-speed camera which can monitor stellar images of the SOFIA main telescope in the visible spectral range at frame rates of up to ~ 300 frames per second. Analysis of image movements at such speeds will help to identify sources of instabilities in flight, such as vibrations and wind loads. Knowledge of such disturbances and their influence on the telescope system will be essential to achieve the requirement of 0.6 arc-seconds (rms) pointing stability.

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Solar Instruments

Select this Article		ChroTel: a robotic telescope to observe the chromosphere of the Sun T. J. Kentischer, Ch. Bethge, D. F. Elmore, R. Friedlein, C. Halbgewachs, M. Knölker, H. Peter, W. Schmidt, M. Sigwarth, and K. Streander Proc. SPIE 7014, 701413 (2008); http://dx.doi.org/10.1117/12.789044 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Chromospheric Telescope (ChroTel) is a 10 cm robotic telescope to observe the full solar disk with a 2k × 2k CCD at high temporal cadence. It is located at the Observatorio del Teide, Tenerife, Spain, next to the 70 cm German Vacuum Tower Telescope (VTT). ChroTel contains a turret system that relays a stabilized image of the solar disk into a laboratory within the VTT building. The control design allows a fully robotic operation. Observations are carried out in three chromospheric wavelengths (CaK: 393 nm, Ha: 652 nm, HeI 1083 nm).

Select this Article		Combination of two Fabry-Perot etalons and a grating spectrograph for imaging polarimetry of the Sun Lucia Kleint, Alex Feller, and Michele Bianda Proc. SPIE 7014, 701414 (2008); http://dx.doi.org/10.1117/12.787923 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Imaging spectroscopy of the Sun is a challenging task usually performed with Fabry-Perot etalons. The common setup is a combination of two or three etalons in series and a narrow-band prefilter. The requirement of one, usually expensive prefilter for every desired wavelength limits the number of spectral regions that can be observed. We present a novel instrument combination consisting of two Fabry-Perot etalons and a grating spectrograph, which allows for observations in any wavelength between 390 nm and 660 nm without the need for narrow-band prefilters. Furthermore, two or more adjacent monochromatic images are projected on the detector, each image corresponding to a different spectral transmission peak of the Fabry-Perot filtergraph. Together with our Zurich Imaging Polarimeter (ZIMPOL) the system is installed at the telescope of the Istituto Ricerche Solari Locarno (IRSOL) where it will be used for two-dimensional spectropolarimetry. We present a description of the instrument and test observations.

Select this Article		Apodized apertures for solar coronagraphy Alexis Carlotti, Claude Aime, Jean Arnaud, Marianne Faurobert, André Ferrari, Catherine Grec, and Gilbert Ricort Proc. SPIE 7014, 701415 (2008); http://dx.doi.org/10.1117/12.789260 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract An apodized aperture should make it possible to observe the solar corona without the need of a Lyot coronagraph. We show in this communication that Sonine functions are much better apodizers for the observation of the solar corona than the generalized prolate spheroidal functions previously proposed. For a perfect circular aperture of diameter unity operated in space, a simple Sonine apodization of the form (1 - 4r²), with \|r\| ≤ 1/2 should sufficiently reduce the diffraction halo produced by the solar disc to observe the corona very close to the solar limb (a few arcsec). The throughput is just one third of the clear aperture.

Select this Article		A new spectro-polarimeter for solar prominence and filament magnetic field measurements David F. Elmore, Roberto Casini, Greg L. Card, Marc Davis, Alice Lecinski, Ron Lull, Peter G. Nelson, and Steven Tomczyk Proc. SPIE 7014, 701416 (2008); http://dx.doi.org/10.1117/12.789556 \| Cited 1 time Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We are constructing a spectro-polarimeter using the 40-cm coronagraph at the Evans Solar Facility of the National Solar Observatory in Sunspot, NM for the purpose of measuring the vector magnetic field in prominences and filaments. The Prominence Magnetometer (ProMag) is comprised of a polarization modulation package and a spectrograph. The modulation optics are located at the prime focus of the coronagraph along with calibration optics and a beamsplitter that creates two beams of orthogonal Stokes states. The spectrograph resides at the coude focus of the coronagraph. The polarizations of the two chromospheric lines of neutral helium, at 587.6 nm and 1083.0 nm, are to be observed simultaneously. We present details of the design of the spectro-polarimeter.

Select this Article		Polarization effects in Fabry-Perot interferometer-based solar spectrometers H.-P. Doerr, O. von der Lühe II, and T. J. Kentischer Proc. SPIE 7014, 701417 (2008); http://dx.doi.org/10.1117/12.789180 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The influence of thin film multilayer coatings of Fabry-Perot interferometers (FPI) on polarimetric measurements is investigated. Because the oblique ray reflectivity of the coatings in general is polarization dependent, the transmission profile is slightly different for the s- and p-components of light passing through the FPI, resulting in weak artificial polarization signals. The difference increases with larger angles of incidence and higher design reflectivity of the coatings. In order to estimate the magnitude of the effect, we perform numerical calculations with different coating designs and different optical configurations. We conclude that while current slow focal ratio solar FPI spectrometers are safe, high-precision polarimetric measurements with large aperture solar telescopes which may require considerably steeper focal ratios may suffer from spurious polarization effects.

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Adaptive Optics Fed Instrumentation and High Contrast Imaging I

Select this Article		SPHERE: a 'Planet Finder' instrument for the VLT Jean-Luc Beuzit, Markus Feldt, Kjetil Dohlen, David Mouillet, Pascal Puget, Francois Wildi, Lyu Abe, Jacopo Antichi, Andrea Baruffolo, Pierre Baudoz, Anthony Boccaletti, Marcel Carbillet, Julien Charton, Riccardo Claudi, Mark Downing, et al. Proc. SPIE 7014, 701418 (2008); http://dx.doi.org/10.1117/12.790120 \| Cited 7 times Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Direct detection and spectral characterization of extra-solar planets is one of the most exciting but also one of the most challenging areas in modern astronomy. The challenge consists in the very large contrast between the host star and the planet, larger than 12.5 magnitudes at very small angular separations, typically inside the seeing halo. The whole design of a "Planet Finder" instrument is therefore optimized towards reaching the highest contrast in a limited field of view and at short distances from the central star. Both evolved and young planetary systems can be detected, respectively through their reflected light and through the intrinsic planet emission. We present the science objectives, conceptual design and expected performance of the SPHERE instrument.

Select this Article		HiCIAO: the Subaru Telescope's new high-contrast coronographic imager for adaptive optics Klaus W. Hodapp, Ryuji Suzuki, Motohide Tamura, Lyu Abe, Hiroshi Suto, Ryo Kandori, Junichi Morino, Tetsuo Nishimura, Hideki Takami, Olivier Guyon, Shane Jacobson, Vern Stahlberger, Hubert Yamada, Richard Shelton, Jun Hashimoto, et al. Proc. SPIE 7014, 701419 (2008); http://dx.doi.org/10.1117/12.788088 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO), is a coronographic simultaneous differential imager for the new 188-actuator AO system at the Subaru Telescope Nasmyth focus. It is designed primarily to search for faint companions, brown dwarves and young giant planets around nearby stars, but will also allow observations of disks around young stars and of emission line regions near other bright central sources. HiCIAO will work in conjunction with the new Subaru Telescope 188-actuator adaptive optics system. It is designed as a flexible, experimental instrument that will grow from the initial, simple coronographic system into more complex, innovative optics as these technologies become available. The main component of HiCIAO is an infrared camera optimized for spectral simultaneous differential imaging that uses a Teledyne 2.5 μm HAWAII-2RG detector array operated by a Sidecar ASIC. This paper reports on the assembly, testing, and "first light" observations at the Subaru Telescope.

Select this Article		LINC-NIRVANA: achieving 10 mas imagery on the Large Binocular Telescope T. M. Herbst, R. Ragazzoni, A. Eckart, and G. Weigelt Proc. SPIE 7014, 70141A (2008); http://dx.doi.org/10.1117/12.788374 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract LINC-NIRVANA is an innovative imaging interferometer fed by dedicated multi-conjugated adaptive optics systems. The instrument combines the light of the two, 8.4-meter primary mirrors of the Large Binocular Telescope (LBT) on a single focal plane, providing panoramic imagery with 23-meter spatial resolution. The instrument employs a number of innovative technologies, including multi-conjugated adaptive optics, state-of-the-art materials, low vibration mechanical coolers, active and passive control, and sophisticated software for data analysis. LINC-NIRVANA is entering its final integration phase, with the large adaptive-optics and imaging subsystems coming together in the clean room in Heidelberg. Here, we report on progress, including insights gained on integration of large instruments.

Select this Article		Conceptual design of IR multi-IFU spectrograph with MOAO Daigo Tomono, Wolfgang Gaessler, and Tetsuo Nishimura Proc. SPIE 7014, 70141B (2008); http://dx.doi.org/10.1117/12.790000 Online Publication Date: Jul 08, 2008 Full Text: \| Download PDF
	+ -	Show Abstract To study properties of cold dark matter (CDM), which can only be observed through its gravitational interaction with galaxies, spatially resolved spectra at least to the K-band are desirable. We started designing a spectrograph which observes multiple targets spatially resolved in a telescope field of view fed with multi-object adaptive optics (MOAO). The current design either places field lenses on the telescope field of view to image the pupil onto steering mirrors, or uses a single set of field lens to deliver beams to pick-off arms. The steering mirror on the pupil image tilts and selects a sub-field from each of the telescope field of view physically split by the field lenses. This allows cheaper and more robust construction of a method to select the target fields with a limitation in selections of the target fields. On the other hand, the pick-off arm implementation allows more flexibility in assigning targets to fields of the integral field units (IFUs) especially when targets are clustered. The IFU arranges spatial elements of each of sub-field of view to be fed into the spectrograph. If enough pixels are afforded, using microlens arrays, which image pupils of spatial elements onto the object plane of the spectrograph is ideal in robustness. Otherwise, an image slicer is to be located to arrange the sub-field of view onto the entrance slit. The instrument should be built as modules to allow expeditious scientific results.

Select this Article		Diffraction limited imaging in the visible from large ground-based telescopes: new methods for future instruments and telescopes Craig Mackay, Nick Law, and Timothy D. Stayley Proc. SPIE 7014, 70141C (2008); http://dx.doi.org/10.1117/12.787439 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Faint object diffraction limited imaging in the visible from the ground has recently been demonstrated on a 5 m telescope with more than twice the resolution of Hubble for the first time. It has shown the way towards diffraction limited imaging in the visible with the next generation of large telescopes. This paper describes the results of experiments to show how this is achieved and what is needed to work well with faint natural guide stars. The importance of a large isoplanatic patch size is also emphasised. In particular, we will describe a new approach to the design of high efficiency, low order adaptive curvature sensors which use photon counting CCD detectors. Such systems used on larger telescopes together with image segmentation and resynthesis techniques using closure phase techniques are shown to have an important place in achieving these goals. The optimum combination of these different techniques will be explained for a variety of different applications.

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Instruments for ELTs I

Select this Article		Early light TMT instrumentation David Crampton, Luc Simard, and David Silva Proc. SPIE 7014, 70141D (2008); http://dx.doi.org/10.1117/12.787605 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Thirty Meter Telescope (TMT) project will provide diffraction limited and seeing limited capabilities that will be highly synergistic with JWST and other planned astronomy missions. TMT will thus be poised to tackle most of the questions confronting scientists today and for the next several decades. The early light instrumentation will provide NIR imaging and integral field spectroscopy designed to sample even the tiny 7mas images provided at 1.2 microns by a multi-conjugate laser guide star AO system, near-infrared multi-slit spectroscopy over a 2 arcmin field (fed by the same AO system, tuned for wide field performance), and wide field multi-object spectroscopy in the 0.3 - 1 micron wavelength region. TMT is being designed, as a system, to take advantage of the observational opportunities that a diffraction limited 30m telescope will afford. Results of detailed end-to-end modeling demonstrate excellent performance in both seeing-limited and diffraction-limited modes. TMT is also being designed to operate in a very efficient manner. Details of how this will be accomplished, descriptions of the planned instrumentation with focus on the early light instruments, new technologies that will be implemented, and a summary of the anticipated observing programs and how these will complement observations from other facilities are described.

Select this Article		Studies for the first generation of instruments for the European ELT Sandro D'Odorico, Mark Casali, Juan-Carlos Gonzales, Markus Kasper, Hans-Ulrich Käufl, Markus Kissler Patig, Luca Pasquini, Suzanne Ramsay, Ralf Siebenmorgen, Joel Vernet, and Filippo M. Zerbi Proc. SPIE 7014, 70141E (2008); http://dx.doi.org/10.1117/12.788422 Online Publication Date: Jul 21, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The European Southern Observatory (ESO) is conducting a phase B study of a European Extremely Large Telescope (E-ELT). The baseline concept foresees a 42m primary, 5 mirror adaptive telescope with two of the mirrors giving the possibility of very fast correction of the atmospheric turbulence. In parallel to the telescope study, ESO is coordinating 8 studies of instruments and 2 of post-focus Adaptive Optics systems, carried out in collaboration with Institutes in the member states. Scope of the studies, to be completed by 1Q 2010, is to demonstrate that the high priority scientific goals of the E-ELT project can be achieved with feasible and affordable instruments. The main observing modes being considered are: NIR wide field imaging and spectroscopy to the diffraction limit or with partial correction of the atmospheric seeing; high spectral resolution, high stability visible spectroscopy; high contrast, diffraction limited imaging and spectroscopy; DL mid-infrared imaging and spectroscopy. The status of the 8 current studies is presented.

Select this Article		Making instruments work on the European ELT Mark M. Casali, Juan Carlos Gonzalez, and Sandro D'Odorico Proc. SPIE 7014, 70141F (2008); http://dx.doi.org/10.1117/12.787765 Online Publication Date: Jul 14, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The title of this paper was chosen to highlight the fact that the installation and operation of instrumentation on Extremely Large Telescopes (ELTs) will not be entirely simple or straightforward. The cost of construction and operation of ELTs will be such that substantial pressures will develop for proportional increases in the level of performance of the instrumentation, using as much of the electromagnetic information arriving at the focal plane as possible. This in turn will require complex instruments using adaptive optics, multiple channels or highly spatially multiplexed instruments. In the case of the European ELT, it will be a facility much in demand by ESOs 4000+ community of astronomers. The instrument infrastructure must therefore be able to accommodate the full range of projects likely to be undertaken. In this paper, we will discuss the instrument interfaces and infrastructure as envisioned in the current baseline for the European ELT and the requirements underpinning them.

Select this Article		An optical design for a wide-field optical spectrograph for TMT Rebecca A. Bernstein and Bruce C. Bigelow Proc. SPIE 7014, 70141G (2008); http://dx.doi.org/10.1117/12.787297 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe a preliminary optical design for a multi-object, wide-field, optical echellette spectrograph that is intended to serve a broad range of science. It will produce low-resolution, single-order spectra for survey-mode programs targeting as many objects as possible and also moderate-resolution, multiple-order spectra for a reduced number of targets. The design uses all refracting optics. The first optical element of the spectrograph is a wide-field corrector for the telescope that causes the chief rays to be perpendicular to the focal plane. The collimator, which has been designed on-axis, can then be duplicated to target multiple, off-axis fields in a multiple-barrel configuration. The collimator optics include an achromatic field lens group that forms a sharp pupil over the full optical band-pass (320-1000 nm), followed by a dichroic which splits the beam into a red and a blue channel. All remaining optical elements of the collimator, the gratings, the cameras, and the detectors are then optimized for red or blue wavelengths. Both red and blue channels of each beam of the spectrograph use reflection gratings to produce either a single-order spectrum at resolutions around R=λ/Δλ=1000 or a five-order, R>5000 echellette spectrum with prism cross-dispersion. Both modes can target objects anywhere in the collimated field of view. A direct imaging mode will also be provided.

Select this Article		Q-Spec: a concept for the Giant Magellan Telescope high resolution optical spectrograph S. Barnes and P. MacQueen Proc. SPIE 7014, 70141H (2008); http://dx.doi.org/10.1117/12.787254 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Q-Spec is a concept for the Giant Magellan Telescope High Resolution Optical Spectrograph. It is a seeing limited, four channel spectrograph designed for high efficiency, high resolution spectroscopy from 305 to 1060 nm. Overall instrument dimensions are minimized with anamorphic preslit optics, pupil slicing, and white pupil beam demagnification. Q-spec uses two 300 × 1600mm R4 echelle grating mosaics of either 2 or 4 individual gratings, with 41.6 and 31.6 grooves/mm line densities. Two beam sizes are selectable in the preslit optics. A 450mm beam yields Rϕ = 30,000 while a 900mm beam reaches Rϕ = 60,000. Both beams are anamorphised before echelle dispersion, and the larger beam is pupil sliced. The post-echelle white pupil transfer optics demagnify the beam by 3. This allows the use of efficient vph grating cross-dispersers, and unvignetted f/1.5-2.0 dioptric cameras with optical element diameters under 250 mm. The bandwidth is split by a dichroic prior to the entrance slit, and by dichroics near the intermediate foci of the two sets of white pupil transfer optics. The four fixed spectral formats have 2-pixel resolving powers of ~200,000 and it is anticipated that resolving powers of R = 150, 000 or greater will be possible. The largest ccd is 6k × 6k with 15 μm pixels, and the minimum order separation is around 10 arcseconds. Q-spec can be fed with fibers in either multiple-object and/or precision radial velocity modes. Excluding the gravity-invariant thermal and vacuum enclosures, the instrument volume is a modest 5 × 2.5 × 2m in size.

Select this Article		CODEX: the high-resolution visual spectrograph for the E-ELT Luca Pasquini, G. Avila, H. Dekker, B. Delabre, S. D'Odorico, A. Manescau, M. Haehnelt, B. Carswell, R. Garcia-Lopez, R. Lopez, M. T. Osorio, R. Rebolo, S. Cristiani, P. Bonifacio, V. D'Odorico, et al. Proc. SPIE 7014, 70141I (2008); http://dx.doi.org/10.1117/12.787936 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract A number of outstanding scientific problems require a high resolution, visual spectrograph at the E-ELT. Measuring the dynamics of the universe, finding earth-like planets with radial velocity techniques, determining the chemical evolution of the intergalactic medium and if physical constants varied in the past, all require a superior capability of measuring exceedingly small Doppler shifts. We have started a Phase A study for CODEX at the E-ELT. We present here the scientific cases, the requirements, the basic technical choices and trade offs, as well as a couple of design under evaluation. We aim at a super stable instrument, capable of obtaining a radial velocity precision of 2 cm/sec over several decades. It will be located at the coude focus. The design will make use of anamorphosis, pupil slicing, slanted VPH gratings and a novel calibration system based on laser frequency combs. Several CODEX-related R&D activities are running, and, in addition, a Call for Proposal for a precursor at the VLT has been issued.

Select this Article		System design and analysis of the exo-planet imaging camera and spectrograph (EPICS) for the European ELT Christophe Vérinaud, Visa Korkiakoski, Natalia Yaitskova, P. Martinez, Markus E. Kasper, Jean-Luc Beuzit, Lyu Abe, Pierre Baudoz, Anthony Boccaletti, Kjetil Dohlen, Raffaele G. Gratton, Dino Mesa, Florian Kerber, Hans Martin Schmid, Lars Venema, et al. Proc. SPIE 7014, 70141J (2008); http://dx.doi.org/10.1117/12.790009 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract One of the main science objectives of the European ELT is the direct imaging of extrasolar planets. The large aperture of the telescope has the potential to significantly enlarge the discovery space towards older gas giant exo-planets seen in reflected light. In this paper, we give an overview of the EPICS system design strategy during the phase A study. In order to tackle the critical limitations to high contrast, extensive end-to-end simulations will be developed since the start to test different scenarios and guide the overall design.

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Instruments for ELTs II

Select this Article		EAGLE: an MOAO fed multi-IFU in the NIR on the E-ELT Jean-Gabriel Cuby, Simon Morris, Ian Bryson, Matthew Lehnert, Chris Evans, Thierry Fusco, Pascal Jagourel, Richard Myers, Gérard Rousset, Hermine Schnetler, Jean-Philippe Amans, Jeremy Allington-Smith, François Assemat, Steven Beard, Fanny Chemla, et al. Proc. SPIE 7014, 70141K (2008); http://dx.doi.org/10.1117/12.787682 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract EAGLE is an instrument under conceptual study for the European Extremely Large Telescope (E-ELT). EAGLE will be installed at the Gravity Invariant Focal Station of the E-ELT, covering a field of view between 5 and 10 arcminutes. Its main scientific drivers are the physics and evolution of high-redshift galaxies, the detection and characterization of first-light objects and the physics of galaxy evolution from stellar archaeology. The top level requirements of the instrument call for 20 spectroscopic channels in the near infrared, assisted by Adaptive Optics. Several concepts of the Target Acquisition sub-system have been studied and are briefly presented. Multi-Conjugate Adaptive Optics (MCAO) over a segmented 5' field has been evaluated and compared to Multi-Object Adaptive Optics (MOAO). The latter has higher performance and is easier to implement, and is therefore chosen as the baseline for EAGLE. The paper provides a status report of the conceptual study, and indicates how the future steps will address the instrument development plan due to be completed within a year.

Select this Article		Optical solutions for the multi-IFU instrument EAGLE for the European ELT Martyn Wells, Sébastien Vives, Eric Prieto, Philippe Laporte, Peter R. Hastings, Chris Evans, Robert Content, and Fanny Chemla Proc. SPIE 7014, 70141L (2008); http://dx.doi.org/10.1117/12.789860 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes the different optical concepts developed for the EAGLE Phase A design. EAGLE will be an MOAO (Multi-object AO) IFU spectrometer operating between 0.8 and 2.5μm. The EAGLE consortium have developed different concepts for the challenging problem of acquiring more than twenty objects in the patrol field of view (FOV), correcting the wavefront along the line of sight to each of the objects and analyzing each object spatially and spectrally with an Integral Field Spectrograph. The target selection FOV will be ≥20 square arcmin and the individual target FOV can be selected to be either 1.65×1.65arcsec or 1.65×3.3arcsec. They will be sampled spatially at 75mas and with spectral resolutions of 4000 and 10000. Optical designs for target acquisition systems, integral-field unit, and spectrographs have been developed. These will be compared and the expected performance will be described in terms of the number of targets, overall patrol field of view, individual field of view, throughput, spectral resolving power and image quality.

Select this Article		METIS: the Mid-infrared E-ELT Imager and Spectrograph Bernhard R. Brandl, Rainer Lenzen, Eric Pantin, Alistair Glasse, Joris Blommaert, Lars Venema, Frank Molster, Ralf Siebenmorgen, Hermann Boehnhardt, Ewine van Dishoeck, Paul van der Werf, Thomas Henning, Wolfgang Brandner, Pierre-Olivier Lagage, Toby J. T. Moore, et al. Proc. SPIE 7014, 70141N (2008); http://dx.doi.org/10.1117/12.789241 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract METIS, the Mid-infrared ELT Imager and Spectrograph (formerly called MIDIR), is a proposed instrument for the European Extremely Large Telescope (E-ELT), currently undergoing a phase-A study. The study is carried out within the framework of the ESO-sponsored E-ELT instrumentation studies. METIS will be designed to cover the E-ELT science needs at wavelengths longward of 3μm, where the thermal background requires different operating schemes. In this paper we discuss the main science drivers from which the instrument baseline has been derived. Specific emphasis has been given to observations that require very high spatial and spectral resolution, which can only be achieved with a ground-based ELT. We also discuss the challenging aspects of background suppression techniques, adaptive optics in the mid-IR, and telescope site considerations. The METIS instrument baseline includes imaging and spectroscopy at the atmospheric L, M, and N bands with a possible extension to Q band imaging. Both coronagraphy and polarimetry are also being considered. However, we note that the concept is still not yet fully consolidated. The METIS studies are being performed by an international consortium with institutes from the Netherlands, Germany, France, United Kingdom, and Belgium.

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Instrumentation Techniques and Technologies I

Select this Article		High-resolution near-IR spectroscopy: from 4m to 40m class telescopes E. Oliva and L. Origlia Proc. SPIE 7014, 70141O (2008); http://dx.doi.org/10.1117/12.788821 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract High resolution (HR) near infrared (NIR) spectroscopy is one of the youngest and less explored fields of astronomical research. The few dedicated instruments which are presently available worldwide have remarkably limited capabilities in terms of spectral coverage. In this paper we discuss some of the most important scientific applications of HR-NIR spectroscopy and present the design of "SIMPLE", a simple (hence its name) and very powerful instrument specifically designed for the E-ELT but which can be easily interfaced to existing 8-10 m class telescopes. We also provide detailed information on the expected performances and limiting magnitudes of SIMPLE on different telescopes.

Select this Article		The FIRST project: a single-mode fiber-based very high-dynamic range diffraction-limited imaging instrument at visible to near-infrared wavelengths Takayuki Kotani, Guy Perrin, Sylvestre Lacour, Eric Thiébaut, Julien Woillez, Pierre Fedou, Jean-Philippe Berger, Pascal Bordé, Olivier Chesneau, Pierre Kervella, Olivier Lai, Alain Lecavelier, Stephen T. Ridgway, Daniel Rouan, and Alfred Vidal-Madjar Proc. SPIE 7014, 70141P (2008); http://dx.doi.org/10.1117/12.789008 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the present status of the development of a very high-dynamic range, diffraction limited imaging instrument FIRST (Fibered Imager foR Single Telescope), among which goals is the detection of nearby extra-solar planets at visible to near-infrared wavelengths from the ground. We have started to develop a prototype system which consists of a number of novel designs such as a segmented micro mirror array and silicon micro machined single-mode fiber arrays. Furthermore, we have proposed to build a FIRST instrument for the CFHT, which will be complementary to high-dynamic range instruments developed for 8m class telescopes at near-infrared wavelengths.

Select this Article		Optimal fabrication of volume phase holographic grism with high efficiency and high dispersion, and its applications for astronomical observation Kaoru Nakajima, Noboru Ebizuka, Masanori Iye, and Kashiko Kodate Proc. SPIE 7014, 70141Q (2008); http://dx.doi.org/10.1117/12.790107 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We had developed three types of large VPH grisms (110×106 mm²) for FOCAS of the 8.2 m Subaru Telescope with high efficiency, high dispersion and small wavefront error in visible region. However, it has been highly difficult to fabricate VPH gratings for longer wavelength due to thickness of the grating. In order to overcome this problem, by optimizing exposure condition and introducing active phase control technique, we had successfully developed VPH grating for optical communication wavelength (1550 nm) with diffraction efficiency over 90% (TE mode) and a high refractive index modulation of 0.047. We extend these techniques to the device for astronomical observation, aiming at the application of K band VPH gratings for MOIRCS of the Subaru Telescope. The resultant grating has attained high diffraction efficiency of 91.5%, spectral bandwidth (FWHM) 320 nm, and small wavefront error 0.03 waves in r.m.s. at 2200 nm. This VPH grism is a promising dispersion device for astronomical observation in near-infrared region.

Select this Article		Slanted fringe volume phase holographic gratings in astronomical instrumentation James A. Arns and Hans Dekker Proc. SPIE 7014, 70141R (2008); http://dx.doi.org/10.1117/12.788804 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Many existing astronomical spectrographs have been retrofitted with volume phase holographic gratings (VPHGs), since at higher line density they are significantly more efficient than surface relief transmission gratings. Designing the spectrograph around the VPHG offers additional advantages. In this paper we describe slanted fringe VPHG that are considered as cross-disperser / beam expander in high-resolution echelle spectrographs for the Combined Incoherent Focus of the VLT and the E-ELT. We will present simulations of diffraction efficiency of slanted fringe VPHGs that explore the useful parameter space of these devices in terms of efficiency, line density and anamorphic beam expansion.

Select this Article		Cryogenic VPH grisms for MOIRCS Takashi Ichikawa, Kotaro Ichiyama, Noboru Ebizuka, Chihiro Murata, Yuichiro Taniguchi, Tsutomu Okura, Masakazu Harashima, Yuka Katsuno Uchimoto, Miyoko Maruyama, Masanori Iye, and Kazuhiro Shimasaku Proc. SPIE 7014, 70141S (2008); http://dx.doi.org/10.1117/12.788051 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the development and first astronomical applications of VPH grisms which are now operated at cryogenic temperature in MOIRCS, a Cassegrain near-infrared instrument of the Subaru Telescope. We designed and fabricated the VPH grisms with a resolving power ~3000 for the use in near-infrared bands. The VPH grating, encapsulated in BK7 glass, is glued between two ZnSe prisms with vertex angle of 20 deg. After repeating several thermal cycles down to ~100 K carefully enough not to cause irreparable damage on the grism during cooling, we evaluated the performance at cryogenic temperature in the laboratory and found no deterioration and no large difference in the performance from that measured in room temperature. Based on commissioning observations with MOIRCS, we have confirmed the high efficiency (~0.8) and the resolving power of the original design. Common use of the grisms is due to start in the second semester of 2008.

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Instrumentation Techniques and Technologies II

Select this Article		The FIREBall fiber-fed UV spectrograph Sarah E. Tuttle, David Schiminovich, Bruno Milliard, Robert Grange, D. Christopher Martin, Shahinur Rahman, Jean-Michel Deharveng, Ryan McLean, Gordon Tajiri, and M. Matuszewski Proc. SPIE 7014, 70141T (2008); http://dx.doi.org/10.1117/12.789836 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FIREBall (Faint Intergalactic Redshifted Emission Balloon) had a successful first engineering flight in July of 2007 from Palestine, Texas. Here we detail the design and construction of the spectrograph. FIREBall consists of a 1m telescope coupled to a fiber-fed ultraviolet spectrograph flown on a short duration balloon. The spectrograph is designed to map hydrogen and metal line emission from the intergalactic medium at several redshifts below z=1, exploiting a small window in atmospheric oxygen absorption at balloon altitudes. The instrument is a wide-field IFU fed by almost 400 fibers. The Offner mount spectrograph is designed to be sensitive in the 195-215nm window accessible at our altitudes of 35-40km. We are able to observe Lyα, as well as OVI and CIV doublets, from 0.3 < z < 0.9. Observations of UV bright B stars and background measurements allow characterization of throughput for the entire system and will inform future flights.

Select this Article		MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system Sean M. Adkins, Judith G. Cohen, Joel Aycock, James Bell, Richard Cohen, Andrew Cooper, Bob Goodrich, Jimmy Johnson, Shui H. Kwok, Jim Lyke, Kevin McCann, Chris Neyman, Tom Nordin, Sergey Panteleev, Grant Tolleth, et al. Proc. SPIE 7014, 70141U (2008); http://dx.doi.org/10.1117/12.789857 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus.

Select this Article		Design and status of the optical corrector for the DES survey instrument P. Doel, T. Abbott, M. Antonik, R. Bernstein, B. Bigelow, D. Brooks, H. Cease, D. L. DePoy, B. Flaugher, M. Gladders, G. Gutierrez, S. Kent, A. Stefanik, A. Walker, and S. Worswick Proc. SPIE 7014, 70141V (2008); http://dx.doi.org/10.1117/12.790049 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The DECam instrument, for the 4m Blanco telescope at CTIO, is a 5 lens element wide field camera giving a 2.2 degree diameter field of view. The lenses are large, with the biggest being 980mm in diameter, and this poses challenges in mounting and alignment. This paper reports the status of the production of the optics for the DECam wide field imager Also presented are the design and finite element modelling of the cell design for the 5 lenses of the imager along with the proposed alignment process.

Select this Article		Deploying comb and tunable lasers to enable precision radial velocity surveys Andrew Szentgyorgyi, Claire Cramer, Andrew Benedick, Alexander G. Glenday, Franz X. Kaertner, Sylvain Korzennik, Chih-Hao Li, Mark P. Ordway, David F. Phillips, Dimitar Sasselov, and Ronald L. Walsworth Proc. SPIE 7014, 70141W (2008); http://dx.doi.org/10.1117/12.789577 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe recent progress toward developing optical frequency laser combs and tunable laser to the problem of more precise calibration of high dispersion astronomical spectra, thus permitting radial velocity determinations in the few cm/sec regime. We describe two programs in progress to calibrate both a cross dispersed echelle spectrograph with a laser comb and to calibrate a multiobject echelle spectrograph with a tunable laser.

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Instrumentation Techniques and Technologies III

Select this Article		X-shooter near-IR spectrograph arm realisation Ramon Navarro, Eddy Elswijk, Niels Tromp, Rik ter Horst, Matthew Horrobin, Joel Vernet, Gert Finger, Paul Groot, and Lex Kaper Proc. SPIE 7014, 70141Y (2008); http://dx.doi.org/10.1117/12.789778 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract X-shooter is a new high-efficiency spectrograph observing the complete spectral range of 300-2500 nm in a single exposure, with a spectral resolving power R>5000. The instrument will be located at the Cassegrain focus of one of the VLT UTs and consists of three spectrographs: UV, VIS and Near-IR. This paper addresses the design, hardware realization and performance of the Near-IR spectrograph of the X-Shooter instrument and its components. Various optical, mechanical and cryogenic manufacturing and verification techniques are discussed. The cryogenic performance of replicated light weight gratings is presented. Bare aluminium mirrors are produced and polished to optical quality to preserve high shape accuracy at cryogenic conditions. Their manufacturing techniques and performance are both discussed. The cryogenic collimator and dispersion boxes, on which the optical components are mounted, feature integrated baffles for improved stiffness and integrated leaf springs to reduce tension on optical components, thereby challenging 5 axis simultaneous CNC milling capabilities. ASTRON Extreme Light Weighting is used for a key component to reduce the flexure of the cryogenic system; some key numbers and unique manufacturing experience for this component are presented. The method of integrated system design at cryogenic working temperatures and the resulting alignment-free integration are evaluated. Finally some key lab test results for the complete NIR spectrograph are presented.

Select this Article		NICI: combining coronagraphy, ADI, and SDI Étienne Artigau, Beth A. Biller, Zahed Wahhaj, Markus Hartung, Thomas L. Hayward, Laird M. Close, Mark R. Chun, Michael C. Liu, Gelys Trancho, François Rigaut, Douglas W. Toomey, and Christ Ftaclas Proc. SPIE 7014, 70141Z (2008); http://dx.doi.org/10.1117/12.788390 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Near-Infrared Coronagraphic Imager (NICI) is a high-contrast AO imager at the Gemini South telescope. The camera includes a coronagraphic mask and dual channel imaging for Spectral Differential Imaging (SDI). The instrument can also be used in a fixed Cassegrain Rotator mode for Angular Differential Imaging (ADI). While coronagraphy, SDI, and ADI have been applied before in direct imaging searches for exoplanets. NICI represents the first time that these 3 techniques can be combined. We present preliminary NICI commissioning data using these techniques and show that combining SDI and ADI results in significant gains.

Select this Article		Lambert: a novel compact calibration solution for superior telescope flat fielding Benjamin J. Haldeman, Joseph R. Tufts, Marton G. Hidas, Matthew A. Dubberley, and Vincent Posner Proc. SPIE 7014, 701420 (2008); http://dx.doi.org/10.1117/12.790007 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Traditional dome flat fielding methods typically have difficulties providing spatially uniform illumination and adequate flux over a telescopic instrument's entire spectral range. Traditional flat fielding screens, with an illumination source at least the size of the primary, can be difficult or impractical to mount and uniformly illuminate. The Las Cumbres Observatory Global Telescope Network (LCOGTN) will consist of approximately 50 robotic telescopes of 0.4 m, 1.0 m, and 2.0 m apertures with instrument bandwidth ranging from 350 - 1800 nm. The network requires a robust flat-field solution to fit in compact enclosures. A scanning illuminated flat fielding bar, Lambert, was developed to meet these requirements. Illumination is from a linear arrangement of sources that are spatially dispersed by a narrow holographic or glass diffuser equal in length to the primary's diameter. We have investigated a linearly scanning, enclosure mounted, deployable unit, and a rotary scanning, telescope mounted unit. For complete visible-light bandwidth, a set of different color LEDs is used. The source density, scan speed, and variable intensity tunes the flux to the instrument wavelength and bandwidth. The Lambert flat fields in comparison to sky flats match pixel to pixel variations better than 0.5%; large scale illumination differences, which are stable and repeatable, are ~1%.

Select this Article		FLEX - the first light explorer: a fully OH-suppressed near-infrared integral field spectrograph Simon C. Ellis, Joss Bland-Hawthorn, Anthony Horton, Roger Haynes, and Andrew McGrath Proc. SPIE 7014, 701421 (2008); http://dx.doi.org/10.1117/12.788527 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FLEX is a concept for a fully OH suppressed near infrared integral field spectrograph, being developed at the AAO. FLEX will be the first instrument to employ fibre Bragg gratings for OH suppression, a radical new technology which cleanly suppresses the atmospheric OH emission lines at 30dB whilst maintaining a high overall throughout of ~90%. In this paper we simulate the expected performance of FLEX, and discuss its impact on the science case. FLEX will effectively make the near-infrared sky 4 mags fainter in the H band and 3 mags fainter in the J band, offering unprecedentedly deep views of the near-infrared Universe. The FLEX concept is optimised for the identification of the sources of first light in the Universe - high redshift galaxies or quasars identified through Lyman-alpha emission or a Lyman break in the continuum spectrum. As such it will consist of a 2x2" integral field unit, composed of a 61 lenslet hexagonal array, feeding an existing moderate spectral resolution spectrograph, via an OH-suppression unit. We have simulated the performance of FLEX and show that it can provide robust identification of galaxies at the epoch of reionisation. A FLEX-like instrument on an ELT could measure the ionisation and enrichment of the inter-galactic medium beyond a redshift of 7 via metal absorption lines.

Select this Article		Design of compact integral field spectrometers for mid- to high-resolving powers using immersed gratings Martyn Wells, Christopher J. Evans, and Peter R. Hastings Proc. SPIE 7014, 701422 (2008); http://dx.doi.org/10.1117/12.787912 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present designs for compact near-IR spectrometers with mid to high resolving powers. They use an innovative combination of integral-field units and immersed gratings, both with and without cross-dispersion. The advent of ELTs with scientific requirements for multi-channel instruments (e.g. EAGLE) with high resolving powers has led to designs for spectrometers which are made more compact by using immersed gratings and are capable of high spectral resolving power by including cross dispersion and an arrangement of the IFU output that provides the requisite short slit.

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Posters: UV/VIS/IR Instrumentation

Select this Article		Lessons learned from VISIR E. Pantin, C. Doucet, H. U. Käufl, P. O. Lagage, R. Siebenmorgen, and M. Sterzik Proc. SPIE 7014, 701424 (2008); http://dx.doi.org/10.1117/12.788785 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract VISIR is the VLT mid-infrared (mid-IR) Imager and Spectrometer. Since 2004, it provides data at high spatial and spectral resolutions in the N (8-13 μm) and Q (16-24 μm) atmospheric windows. VISIR observations have provided unique constraints on targets such as central regions of nearby galaxies, or protoplanetary disks. We review here VISIR Imager and Spectrometer characteristics, emphasizing on some current limitations because of various undesirable effects. Its successor on an ELT will provide data with a unique sharpness (0.05") and sensitivity (35 μJy source detectable in 1 hour at 10 σ level), thus allowing a characterization of exoplanetary disks and inner exoplanets with an unprecedent precision. At the light of VISIR experience, we discuss how the lessons learned from VISIR can be turned to good account for designing and operating the future mid-IR instrument on the European ELT.

Select this Article		LIINUS/SERPIL: a design study for interferometric imaging spectroscopy at the LBT F. Müller Sánchez, C. Gál, F. Eisenhauer, A. Krabbe, M. Haug, C. Iserlohe, and T. M. Herbst Proc. SPIE 7014, 701425 (2008); http://dx.doi.org/10.1117/12.788061 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present two design concepts and the science drivers of a proposed near-infrared interferometric integral field spectrograph for the LBT. This instrument will expand the capabilities of the currently-under-construction interferometric camera LINC-NIRVANA with spectroscopy by means of an integral field unit (IFU) located inside the LINC cryostat. Two instrument concepts have been studied in detail: a microlens array IFU with a spectrograph built entirely inside LINC (the LIINUS approach), and a lenslet+fibers IFU feeding an external spectrograph (the SERPIL approach). In both cases, the instrument incorporates imaging interferometry with integral field spectroscopy, an ideal combination for detailed studies of astronomical objects down to below 10mas angular resolution in the near-infrared. The scientific applications range from solar system studies and spectroscopy of exoplanets to the dynamics of stars and gas in the central regions of the Milky Way and other nearby galaxies.

Select this Article		Fabrication of slicer optics of mid-infrared spectrometer with an image slicer (MIRSIS) for ground-based astronomy Kenji Mitsui, Norio Okada, Mitsuhiro Fukushima, Tetsuo Nishino, Yoshiko Kataza Okamoto, Hirokazu Kataza, and Takashi Onaka Proc. SPIE 7014, 701427 (2008); http://dx.doi.org/10.1117/12.787724 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Mid Infrared Spectrometer with an Image Slicer (MIRSIS) is a compact mid-infrared spectrometer with an image slicer as a testbed of techniques for efficient observations with next generation telescopes. MIRSIS is a 10-micron band spectrometer for ground-based observations. Optics of MIRSIS is mostly composed of reflective ones. A key point of the development of MIRSIS is a fabrication of slicer optics, which consists of slice mirrors, pupil mirrors and pseudo slit mirrors. It is necessary to develop fabrication technique of slicer optics, because shapes and alignment of these mirrors are special. Here it is also important to choose the design matched to the processing method. In this paper, we report our fabrication of the slicer optics elements in detail. As a result, we achieved the slice mirror with the micro-roughness of RMS 12nm and the angle accuracy of under 0.0041deg, the pupil mirror with the micro-roughness of RMS 20nm and the shape accuracy of PV 3micron, and the pseudo slit mirror with the angle accuracy of 0.02deg. All of the parts fabricated satisfy the required specification.

Select this Article		A new mid-infrared camera for ground-based 30 micron observations: MAX38 Takashi Miyata, Shigeyuki Sako, Tomohiko Nakamura, Takashi Onaka, and Hirokazu Kataza Proc. SPIE 7014, 701428 (2008); http://dx.doi.org/10.1117/12.787739 \| Cited 3 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We are developing a new infrared camera MAX38 (Mid-infrared Astronomical eXplorer) for long mid-infrared (25-40 micron) astronomy for the Univ. of Tokyo Atacama 1.0-meter telescope which is the world highest infrared telescope at 5,640m altitude. Thanks to the high altitude and dry weather condition of the Atacama site we can access the 30-micron wavelength region from ground-based telescopes for the first time in the world. We employ a Si:Sb 128×128 array detector to cover the wide mid-infrared wavelength range from 8 to 38 micron. The development of the MAX38 has been almost completed. Test observations in N-band wavelength at Hiroshima Kanata telescope (Hiroshima, Japan) was successfully carried out on June 2007 and March 2008. The first 30-micron observation at Atacama is scheduled in the spring of 2009.

Select this Article		A mid-infrared polarization capability for the ELT Christopher M. Wright, Ralf Siebenmorgen, Bringfried Stecklum, Michael Sterzik, and Hans-Ulrich Käufl Proc. SPIE 7014, 701429 (2008); http://dx.doi.org/10.1117/12.787899 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Imaging- and spectropolarimetry in the thermal infrared (~ 5-30 μm) can inform us about two important open questions in modern astrophysics - namely the role of magnetism in the formation of stars, and the life-cycle of cosmic dust. These are key questions outlined in the document "A Science Vision for European Astronomy" by de Zeeuw & Molster (2007). Thermal IR polarimetry is the only technique that can peer into the heart of star forming cores, where an infant star heats its immediate surroundings to temperatures of several hundred Kelvin. The polarization itself is induced by a preferential alignment of the spin axis of cosmic dust grains, a process ultimately controlled by the ambient magnetic field. The spectrum is sensitively dependent on the grain optical properties, structure and shape, thus providing information not otherwise obtainable by conventional spectroscopy. The MIRI instrument on the JWST will not have a polarimetry mode, thus leaving open the possibility of an ELT mid-IR instrument being able to make substantial progress on these fundamental issues. Before describing the advantages of a mid-IR spectropolarimeter on an ELT, we first present some preliminary results from our polarization observations with the TIMMI2 mid-IR instrument between 2004 and 2006. The experience gained with TIMMI2 - in terms of technical issues and observing strategy - will inform the design of any future instrument. Following this we will describe the science that could be done with an ELT instrument, and some of the basic design parameters. For instance, with a resolution of ~ 70 milli-arcseconds (FWHM at 10 μm) it will become possible to resolve the magnetic field configuration in the circumstellar disks and bipolar outflows of young stars at a spatial scale of less than 10 AU in the nearest star formation regions. This will strongly constrain hydromagnetic models - the favoured means of extracting angular momentum and allowing accretion to proceed - for bipolar jets emanating from a range of compact astrophysical objects. Further, with a resolving power of order 200, and sensitivity of 100σ in 1 hour integration on a 0.5 mJy point source, the evolution of cosmic dust - and the governing physical and chemical processes - from its formation in old stellar outflows to its deposition in planet-forming disks, will become amenable to detailed polarization studies.

Select this Article		A large free-standing wire grid for microwave variable-delay polarization modulation G. M. Voellmer, C. Bennett, D. T. Chuss, J. Eimer, H. Hui, S. H. Moseley, G. Novak, E. J. Wollack, and L. Zeng Proc. SPIE 7014, 70142A (2008); http://dx.doi.org/10.1117/12.787979 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract One technique for mapping the polarization signature of the cosmic microwave background uses large, polarizing grids in reflection. We present the system requirements, the fabrication, assembly, and alignment procedures, and the test results for the polarizing grid component of a 50 cm clear aperture, Variable-delay Polarization Modulator (VPM). This grid is being built and tested at the Goddard Space Flight Center as part of the Polarimeter for Observing Inflationary Cosmology at the Reionization Epoch (POINCARE). For the demonstration instrument, 64 μm diameter tungsten wires are being assembled into a 200 μm pitch, free-standing wire grid with a 50 cm clear aperture, and an expected overall flatness better than 30 μm. A rectangular, aluminum stretching frame holds the wires with sufficient tension to achieve a minimum resonant frequency of 185 Hz, allowing VPM mirror translation frequencies of several Hz. A lightly loaded, flattening ring with a 50 cm inside diameter rests against the wires and brings them into accurate planarity.

Select this Article		Development of mid-infrared spectrometer with an image slicer (MIRSIS) for ground-based astronomy: developing optical and mechanical mounts Yoshiko Kataza Okamoto, Hirokazu Kataza, Keigo Sato, Kei Manabe, Kenji Mitsui, Norio Okada, Mitsuhiro Fukushima, Tetsuo Nishino, Koji Tomita, Masamune Tosa, and Takashi Onaka Proc. SPIE 7014, 70142B (2008); http://dx.doi.org/10.1117/12.788575 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Mid-Infrared Spectrometer with an Image Slicer (MIRSIS) is a 10micron band spectrometer for ground-based observations. Based on the optical design reported in Okamoto et al. (2006), we recently developed most of optical elements and their mounts. There, we adopted designs based on an ultra-precision cut for the slice mirrors and the pupil mirrors. We also designed and partly manufactured the optical parts with switching/adjusting mechanism with cryogenic step motors. Since MIRSIS has a very complicated stereoscopic configuration of optical elements, we developed a method to adjust the optical alignment where relative positional markers and a three-dimensional measuring system are combined. We confirmed that we can achieve position and angular adjustment with error down to 0.1mm and 0.05degree through alignment test with a pair of mirrors.

Select this Article		A silicon and KRS-5 grism suite for FORCAST on SOFIA Casey P. Deen, Luke Keller, Kimberly A. Ennico, Daniel T. Jaffe, Jasmina P. Marsh, Joseph D. Adams, Nirbhik Chitrakar, Thomas P. Greene, Douglas J. Mar, and Terry Herter Proc. SPIE 7014, 70142C (2008); http://dx.doi.org/10.1117/12.788565 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have designed and fabricated a suite of grisms for use in FORCAST, a mid-infrared camera scheduled as a first-light instrument on SOFIA. The grism suite gives SOFIA a new capability: low and moderate resolution spectroscopy from 5μm to 37μm, without the addition of a new instrument. One feature of the optical design is that it includes a mode using pairs of cross-dispersed grisms, providing continuous wavelength coverage over a broad range at higher resolving power. We fabricated four silicon (n = 3.44) grisms using photolithographic techniques and purchased two additional mechanically ruled KRS-5 (n = 2.3) grisms. One pair of silicon grisms permits observations of the 5 - 8μm band with a long slit at R~ 200 or, in a cross-dispersed mode, at resolving powers up to 1500. In the 8 - 14μm region, where silicon absorbs heavily, the KRS-5 grisms produce resolving powers of 300 and 800 in long-slit and cross-dispersed mode, respectively. The remaining two silicon grisms cover 17 - 37μm at resolving powers of 140 and 250. We have thoroughly tested the silicon grisms in the laboratory, measuring efficiencies in transmission at 1.4 - 1.8μm. We report on these measurements as well as on cryogenic performance tests of the silicon and KRS-5 devices after installation in FORCAST.

Select this Article		Direct thermal imaging of circumstellar discs and exo-planets Eric Pantin, Ralf Siebenmorgen, Celine Cavarroc, and Michael F. Sterzik Proc. SPIE 7014, 70142D (2008); http://dx.doi.org/10.1117/12.788826 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The phase A study of a mid infrared imager and spectrograph for the European Extremely Large Telescope (E-ELT), called METIS, was endorsed in May 2008. Two key science drivers of METIS are: a) direct thermal imaging of exo-planets and b) characterization of circumstellar discs from the early proto-planetary to the late debris phase. Observations in the 10μm atmospheric window (N band) require a contrast ratio between stellar light and emitted photons from the exo-planet or the disc of ~ 10⁵. At shorter wavelengths the contrast between star and reflected light from the planet-disc system exceeds ≳ 10⁷ posing technical challenges. By means of end-to-end detailed simulations we demonstrate that the superb spatial resolution of a 42m telescope in combination with stellar light rejection methods such as coronagraphic or differential imaging will allow detections at 10μm for a solar type system down to a star-planet separation of 0.1" and a mass limit for irradiated planets of 1 Jupiter (M_J) mass. In case of self-luminous planets observations are possible further out e.g. at the separation limit of JWST of ~ 0.7", METIS will detect planets ≳5M_J. This allows to derive a census of all such exo-planets by means of thermal imaging in a volume limited sample of up to 6pc. In addition, METIS will provide the possibility to study the chemical composition of atmospheres of exo-planets using spectroscopy at moderate spectral resolution (λ/Δλ ~ 100) for the brightest targets. Based on detailed performance and sensitivity estimates, we demonstrate that a mid-infrared instrument on an ELT is perfectly suited to observe gravitationally created structures such as gaps in proto- and post- planetary discs, in a complementary way to space missions (e.g. JWST, SOFIA) and ALMA which can only probe the cold dust emission further out.

Select this Article		Laboratory performance characteristics of CanariCam, the GTC facility multi-mode mid-IR camera Margaret M. Moerchen, Christopher Packham, Charles M. Telesco, Kevin T. Hanna, Jeffrey A. Julian, Frank Varosi, James H. Hough, Francisco Reyes, Christ Ftaclas, J. G. Bennett, Roger E. Julian, Charles Murphey, and Craig Warner Proc. SPIE 7014, 70142E (2008); http://dx.doi.org/10.1117/12.789040 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract CanariCam is the facility multi-mode mid-IR camera developed by the University of Florida (UF) for the 10.4- meter Gran Telescopio Canarias (GTC). CanariCam contains a 320 × 240-pixel Raytheon array, which will Nyquist-sample the diffraction-limited point-spread-function at wavelengths longer than 8 microns, yielding a field of view of 26"×19". In Aug. 2007, the University of Florida instrument team held a successful Acceptance Testing (AT) of CanariCam. We describe key performance requirements, and compare these to the actual performance during formal AT. Among the results considered are detector noise characteristics, image quality, and throughput. We focus particularly on the unique dual-beam polarimetric modes. We have demonstrated that with a half-wave plate, it achieves or exceeds the design goals for imaging both polarization planes simultaneously.

Select this Article		FORCAST: the first light instrument for SOFIA Joseph D. Adams, Terry L. Herter, George E. Gull, Justin Schoenwald, Luke D. Keller, Marc Berthoud, Gordon J. Stacy, Thomas Nikola, and Charles P. Henderson Proc. SPIE 7014, 70142F (2008); http://dx.doi.org/10.1117/12.789510 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FORCAST has been selected to be the "first light" U.S. science instrument aboard SOFIA. FORCAST will offer dual channel imaging in discrete filters at 5 - 25 microns and 30 - 40 microns, with diffraction-limited imaging at wavelengths > 15 microns. FORCAST will have a plate scale of 0.75 arcsec per pixel, giving it a 3.2 arcmin x 3.2 arcmin FOV on SOFIA. We give a status update on FORCAST, including filter configuration for SOFIA's early science phase; anticipated in-flight performance; SOFIA facility testing with FORCAST; ground-based testing performance at Palomar Observatory; performance of its new dichroic beamsplitter; and a preliminary design of the in-flight calibration box.

Select this Article		Optical properties of astronomical silicates S. Rinehart, D. Benford, E. Dwek, R. Henry, J. Nuth, R. Silverberg, and E. Wollack Proc. SPIE 7014, 70142G (2008); http://dx.doi.org/10.1117/12.789712 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Correct interpretation of a vast array of astronomical data relies heavily on understanding the properties of silicate dust as a function of wavelength, temperature, and crystallinity. We introduce the OPASI-T (Optical Properties of Astronomical Silicates with Infrared Techniques) project to address the need for high fidelity optical characterization data on the various forms of astronomical dust. We use two spectrometers to provide extinction data for silicate samples across a wide wavelength range (from the near infrared to the millimeter). New experiments are in development that will provide complementary information on the emissivity of our samples, allowing us to complete the optical characterization of these dust materials. In this paper, we present initial results from several materials including amorphous iron silicate, magnesium silicate and silica smokes, over a wide range of temperatures, and discuss the design and operation of our new experiments.

Select this Article		Design of a mid-IR polarimeter for SOFIA C. Packham, M. Escuti, G. Boreman, I Quijano, J. C. Ginn, B. Franklin, D. J. Axon, J. H. Hough, T. J. Jones, P. F. Roche, M. Tamura, C. M. Telesco, N. Levenson, J. M. Rodgers, and J. P. McGuire Proc. SPIE 7014, 70142H (2008); http://dx.doi.org/10.1117/12.789843 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Mid-infrared polarimetry remains an underexploited technique; where available it is limited in spectral coverage from the ground, and conspicuously absent from the Spitzer, JWST and Herschel instrument suites. The unique characteristics of SOFIA afford unprecedented spectral coverage and sensitivity in the mid-infrared waveband. We discuss the preliminary optical design for a 5-40μm spectro-polarimeter for use on SOFIA, the SOFIA Mid-InfraRed Polarimeter (SMIRPh). The design furthers the existing 5-40μm imaging and spectroscopic capabilities of SOFIA, and draws on experience gained through the University of Florida's mid-IR imagers, spectrometer and polarimeter designs of T-ReCS and CanariCam. We pay special attention to the challenges of obtaining polarimetric materials suitable at both these wavelengths and cryogenic temperatures. Finally, we (briefly) present an overview of science highlights that could be performed from a 5-40μm imaging- and spectro-polarimeter on SOFIA. Combined with the synergy between the possible future far-IR polarimeter, Hale, this instrument would provide the SOFIA community with unique and exciting science capabilities, leaving a unique scientific legacy.

Select this Article		Science of active galactic nuclei with the GTC and CanariCam Nancy A. Levenson, Christopher C. Packham, Almudena Alonso-Herrero, Itziar Aretxaga, Luis Colina, Tanio Díaz-Santos, Moshe Elitzur, Rachel E. Mason, Eric S. Perlman, James T. Radomski, Patrick F. Roche, José Miguel Rodríguez Espinosa, Stuart Young, and Charles M. Telesco Proc. SPIE 7014, 70142I (2008); http://dx.doi.org/10.1117/12.790123 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract CanariCam is the facility mid-infrared (MIR) instrument for the Gran Telescopio Canarias (GTC), a 10.4m telescope at the Observatorio del Roque de los Muchachos on La Palma. One of the science drivers for CanariCam is the study of active galactic nuclei (AGN). We will exploit the instrument's high sensitivity in imaging, spectroscopy, and polarimetry modes to answer fundamental questions of AGN and their host galaxies. Dust in the nucleus of an active galaxy reprocesses the intrinsic radiation of the central engine to emerge in the MIR. Current work demonstrates that the hot dust immediately associated with the AGN, which blocks direct views of the AGN from some lines of sight, is confined to small (parsec) scales. Thus, high spatial resolution is essential to probe the "torus" of unified AGN models separate from the host galaxy. CanariCam provides a 0.08" pixel scale for Nyquist sampling the diffraction-limited point spread function at 8μm, and narrow (0.2") spectroscopy slits (with R=120-1300). New observations with the GTC/CanariCam will provide key constraints on the physical conditions in the clumpy torus, and we will sensitively determine AGN obscuration as a function of nuclear activity. We will therefore address the fueling process and its relationship to the torus, the interaction with the host galaxy, and dust chemistry. These data will be essential preparation for the next generation of telescopes that will observe the distant universe directly to explore galaxy and black hole formation and evolution, and the GTC/CanariCam system uniquely provides multiple modes to probe AGN.

Select this Article		10 meter airborne observatory Thomas D. Ditto and Joseph M. Ritter Proc. SPIE 7014, 70142J (2008); http://dx.doi.org/10.1117/12.790261 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Inside an aircraft fuselage there is little room for the mass of all the instrumentation of a ground-based observatory much less a primary objective aperture at the scale of 10 meters. We have proposed a solution that uses a primary objective grating (POG) which matches the considerable length of the aircraft, approximately 10 meters, and conforms to aircraft aerodynamics. Light collected by the POG is diffracted at an angle of grazing exodus inside the aircraft where it is disambiguated by an optical train that fits within to the interior tunnel. Inside the aircraft, light is focused by a parabolic mirror onto a spectrograph slit. The design has a special benefit in that all objects in the field-of-view of the free spectral range of the POG can have their spectra taken as the aircraft changes orientation. We suggest flight planes that will improve integration times, angular resolution and spectral resolution to acquire targets of high stellar magnitudes or alternatively increase the number of sources acquired per flight at the cost of sensitivity.

Select this Article		Solving the three cross-talk flavors on WIRCam and its HAWAII-2RG detectors Loïc Albert, Marc Baril, Jeff Ward, Stéphane Arnouts, and Daniel Devost Proc. SPIE 7014, 70142K (2008); http://dx.doi.org/10.1117/12.787670 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Wide field Infrared Camera (WIRCam) is one of the 3 workhorse instruments in operation at CFHT. It's mosaic of four HAWAII-2RG is read using two SDSU-III controllers with 32-amplifiers in parallel per detector. First-light images showed that WIRCam suffered from three flavors of cross-talk: the "positive", "negative" and "edge" cross-talks. All have now been eliminated at the source and WIRCam is now cross-talk free. Two of these cross-talks originated from the controller electronic and one, the "edge" cross-talk, is intimately linked to the HAWAII-2RG detector and its description may be of a broader interest for other instruments using these detectors. We present the three cross-talk flavors and the hardware or software solutions implemented to eliminate them.

Select this Article		The Canarias InfraRed Camera Experiment (CIRCE): progress of the opto- and cryo- mechanical design and manufacture M. L. Edwards, S. S. Eikenberry, M. Charcos-Llorens, A. Marin-Franch, N. Lasso, S. N. Raines, J. Julian, K. Hanna, C. Packham, M. Rodgers, and R. M. Bandyopadhyay Proc. SPIE 7014, 70142L (2008); http://dx.doi.org/10.1117/12.788424 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the current status of the Canarias InfraRed Camera Experiment (CIRCE) an all-reflective near-IR, imager, spectrograph, and polarimeter for the 10.4-meter Gran Telescopio Canarias (GTC). In particular, we review the progress of the opto- and cryo- mechanical design and manufacture, focusing on the custom filter, lyot, and grism wheels, lightweight optics, and mirror brackets. We also outline our progress with the optical bench. Finally, we discuss a number of CIRCE's features that both complement and augment the planned suite of GTC facility instruments.

Select this Article		Polarimetric capabilities with the Canarias InfraRed Camera Experiment (CIRCE) Miguel V. Charcos-Llorens, Stephen S. Eikenberry, Michelle L. Edwards, Nestor M. Lasso, Antonio Marin-Franch, and Christopher C. Packham Proc. SPIE 7014, 70142M (2008); http://dx.doi.org/10.1117/12.788350 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Canarias InfraRed Camera Experiment (CIRCE) for the Gran Telescopio Canarias (GTC) is one of the few infrared instruments in the world using a four-beam polarimeter. The classical double-beam configuration consists of a half-wave plate (HWP) and a Wollaston Prism (WP) that allow measurement of two linear polarization components of the light in a single exposure. Instead, our instrument includes a WeDoWo - a dual-WP system with principal axis at 45 degrees that is inserted near the pupil plane. Thus, all linear Stokes parameters can be obtained in a single observation. We can also perform medium-resolution (R=400-1500) spectro-polarimetry by inserting a grism in the beam. The CIRCE focal plane mask includes three field stops for imaging polarimetry, three slits for spectropolarimetry and three slits for regular spectroscopy of nearby sources. CIRCE also has a high-speed photometry mode that, combined with polarimetry on a large telescope such as the GTC, will provide important insights into highly-variable sources such as microquasars.

Select this Article		Readout electronics and fast photometry with the Canarias InfraRed Camera Experiment (CIRCE) Nestor M. Lasso Cabrera, Kevin T. Hanna, Stephen S. Eikenberry, Michelle L. Edwards, Miguel V. Charcos-Llorens, Antonio Marin-Franch, and Javier Cenarro Proc. SPIE 7014, 70142N (2008); http://dx.doi.org/10.1117/12.788367 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design for a high-speed readout imaging mode for the Canarias InfraRed Camera Experiment (CIRCE), a visitor-class near-IR imager, spectrograph, and polarimeter for the 10.4 meter Gran Telescopio Canarias (GTC). This mode, along with the polarimetric and spectroscopic capabilities of the instrument will provide a powerful and unique instrument for the study of fast variability objects. Modification in the firmware of the readout control electronics of the HAWAII-2 2048×2048 detector will allow us to select the effective detector size and hence reduce the readout time. We present a description of the final design along with a discussion of potential future improvements.

Select this Article		AIR-C: Antarctic infra-red camera Ramsey Lundock and Takashi Ichikawa Proc. SPIE 7014, 70142O (2008); http://dx.doi.org/10.1117/12.786509 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This paper details the design process for AIR-C, the Antarctic Infra-Red Camera, for use with Tohoku University's 40 cm Antarctic telescope. The camera will also be compatible with the planned 2 meter class Japanese telescope at Dome F. First, we review of the design requirements which shaped the development process. The optical chain receives the most detailed discussion. The other components will be discussed briefly. The effect of cryogenic temperatures on the lenses was taken into account during the design process. AIR-C's performance is predicted. Finally, we discuss the scientific potential for a small Antarctic telescope.

Select this Article		Smithsonian Widefield Infrared Camera Warren R. Brown, Brian A. McLeod, John C. Geary, and Emily C. Bowsher Proc. SPIE 7014, 70142P (2008); http://dx.doi.org/10.1117/12.787117 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Smithsonian Widefield Infrared Camera (SWIRC) is a Y -, J-, and H-band imager for the f/5 MMT. Proposed in May 2003 and commissioned in June 2004, the goal of the instrument was to deliver quickly a wide field-of-view instrument with minimal optical elements and hence high throughput. The trade-off; was to sacrifice K-band capability by not having an internal, cold Lyot stop. We describe SWIRC's design and capabilities, and discuss lessons learned from the thermal design and the detector mount, all of which have been incorporated into the upcoming MMT & Magellan Infrared Spectrograph.

Select this Article		Preliminary optical design of PANIC, a wide-field infrared camera for CAHA M. C. Cárdenas, J. Rodríguez Gómez, R. Lenzen, and E. Sánchez-Blanco Proc. SPIE 7014, 70142Q (2008); http://dx.doi.org/10.1117/12.787390 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, we present the preliminary optical design of PANIC (PAnoramic Near Infrared camera for Calar Alto), a wide-field infrared imager for the Calar Alto 2.2 m telescope. The camera optical design is a folded single optical train that images the sky onto the focal plane with a plate scale of 0.45 arcsec per 18 μm pixel. A mosaic of four Hawaii 2RG of 2k x 2k made by Teledyne is used as detector and will give a field of view of 31.9 arcmin x 31.9 arcmin. This cryogenic instrument has been optimized for the Y, J, H and K bands. Special care has been taken in the selection of the standard IR materials used for the optics in order to maximize the instrument throughput and to include the z band. The main challenges of this design are: to produce a well defined internal pupil which allows reducing the thermal background by a cryogenic pupil stop; the correction of off-axis aberrations due to the large field available; the correction of chromatic aberration because of the wide spectral coverage; and the capability of introduction of narrow band filters (~1%) in the system minimizing the degradation in the filter passband without a collimated stage in the camera. We show the optomechanical error budget and compensation strategy that allows our as built design to met the performances from an optical point of view. Finally, we demonstrate the flexibility of the design showing the performances of PANIC at the CAHA 3.5m telescope.

Select this Article		PANIC: the new panoramic NIR camera for Calar Alto Harald Baumeister, Matthias Alter, M. Concepción Cárdenas Vázquez, Matilde Fernandez, Josef Fried, Jens Helmling, Armin Huber, Jose-Miguel Ibáñez Mengual, Julio F. Rodríguez Gómez, Werner Laun, Rainer Lenzen, Ulrich Mall, Vianak Naranjo, Jose-Ricardo Ramos, Ralf-Rainer Rohloff, et al. Proc. SPIE 7014, 70142R (2008); http://dx.doi.org/10.1117/12.788796 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract PANIC is a wide-field NIR camera, which is currently under development for the Calar Alto observatory (CAHA) in Spain. It uses a mosaic of four Hawaii-2RG detectors and covers the spectral range from 0.8-2.5 μm (z to K-band). The field-of-view is 30×30 arcmin. This instrument can be used at the 2.2m telescope (0.45arcsec/pixel, 0.5×0.5 degree FOV) and at the 3.5m telescope (0.23arcsec/pixel, 0.25×0.25 degree FOV). The operating temperature is about 77K, achieved by liquid Nitrogen cooling. The cryogenic optics has three flat folding mirrors with diameters up to 282 mm and nine lenses with diameters between 130 mm and 255 mm. A compact filter unit can carry up to 19 filters distributed over four filter wheels. Narrow band (1%) filters can be used. The instrument has a diameter of 1.1 m and it is about 1 m long. The weight limit of 400 kg at the 2.2m telescope requires a light-weight cryostat design. The aluminium vacuum vessel and radiation shield have wall thicknesses of only 6 mm and 3 mm respectively.

Select this Article		First light with NEWFIRM Ronald G. Probst, James R. George, Philip N. Daly, Ken Don, and Maureen Ellis Proc. SPIE 7014, 70142S (2008); http://dx.doi.org/10.1117/12.787473 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract NEWFIRM, the widefield infrared camera for the NOAO 4-m telescopes, saw first light in February 2007 and is now in service as a general user instrument. Previous papers have described it conceptually and presented design details. We discuss experience gained from assembly, laboratory testing, and on-sky commissioning. We present final system performance characteristics and summarize science use in its the first semester of general availability. NEWFIRM has met its requirement to provide a high efficiency observing system, optimized end-to-end for survey science.

Select this Article		ANIR: Atacama near infrared camera for Paschen α imaging Kentaro Motohara, Natsuko Mitani, Shigeyuki Sako, Yuka K. Uchimoto, Koji Toshikawa, Tomoyasu Yamamuro, Toshihiro Handa, Masuo Tanaka, Tsutomu Aoki, Mamoru Doi, Kimiaki Kawara, Kotaro Kohno, Takeo Minezaki, Takashi Miyata, Takao Soyano, et al. Proc. SPIE 7014, 70142T (2008); http://dx.doi.org/10.1117/12.788517 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have been developing a near infrared camera called ANIR (Atacama Near InfraRed camera), for the University of Tokyo Atacama 1.0m telescope installed at the summit of Co. Chajnantor (5640m altitude) in Northern Chile. The major aim of this camera is to carry out an imaging survey in Paschen α emission line (1.8751μm) from the ground for the first time. The camera is based on a PACE-HAWAII2 array with an Offner relay optics for re-imaging, and field of view is 5.'3 × 5.'3 with pixel scale of 0."308/pix. It is scheduled to see first light in the end of 2008, and start the Paschen α/β survey of the Galactic plane in 2009.

Select this Article		The FourStar infrared camera S. E. Persson, Robert Barkhouser, Christoph Birk, Randy Hammond, Albert Harding, E. R. Koch, J. L. Marshall, Patrick J. McCarthy, David Murphy, Joe Orndorff, Gregg Scharfstein, Stephen A. Shectman, Stephen Smee, and Alan Uomoto Proc. SPIE 7014, 70142V (2008); http://dx.doi.org/10.1117/12.790015 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The FourStar infrared camera is a 1.0-2.5 μm (JHK_s) near infrared camera for the Magellan Baade 6.5m telescope at Las Campanas Observatory (Chile). It is being built by Carnegie Observatories and the Instrument Development Group and is scheduled for completion in 2009. The instrument uses four Teledyne HAWAII-2RG arrays that produce a 10.9' × 10.9' field of view. The outstanding seeing at the Las Campanas site coupled with FourStar's high sensitivity and large field of view will enable many new survey and targeted science programs.

Select this Article		Performance of the WIYN high-resolution infrared camera Margaret Meixner, Stephen Smee, Ryan L. Doering, Robert H. Barkhouser, Todd Miller, Joseph Orndoff, Patricia Knezek, Edward Churchwell, Gregg Scharfstein, Jeff Percival, David Mills, and Charles Corson Proc. SPIE 7014, 70142W (2008); http://dx.doi.org/10.1117/12.790224 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design overview and on-telescope performance of the WIYN High Resolution Infrared Camera (WHIRC). As a dedicated near-infrared (0.8-2.5 μm) camera on the WIYN Tip-Tilt Module (WTTM), WHIRC will provide near diffraction-limited imaging with a typical FWHM of ~0.25". WHIRC uses a 2048 x 2048 HgCdTe array from Raytheon's VIRGO line, which is a spinoff from the VISTA project. The WHIRC filter complement includes J, H K_S, and 10 narrowband filters. WHIRC's compact design makes it the smallest near-IR camera with this capability. We determine a gain of 3.8 electrons ADU^-1 via a photon transfer analysis and a readout noise of ~27 electrons. A measured dark current of 0.23 electrons s^-1 indicates that the cryostat is extremely light tight. A plate scale of 0.098" pixel^-1 results in a field of view (FOV) of ~3' x 3', which is a compromise between the highest angular resolution achievable and the largest FOV correctable by WTTM. Measured throughput values (~0.33 in H-band) are consistent with those predicted for WHIRC based on an elemental analysis. WHIRC was delivered to WIYN in July 2007 and was opened for shared risk use in Spring 2008. WHIRC will be a facility instrument at the WIYN telescope enabling high definition near-infrared imaging studies of a wide range of astronomical phenomena including star formation regions, proto-planetary disks, stellar populations and interstellar medium in nearby galaxies, and supernova and gamma-ray burst searches.

Select this Article		Cryogenic tests of bimetallic diamond-turned mirrors for the FRIDA integral field unit Curtis DeWitt, Stephen Eikenberry, Salvador Cuevas Cardona, Oscar Chapa, Carlos Espejo, Carolina Keiman, and Beatriz Sanchez Proc. SPIE 7014, 70142X (2008); http://dx.doi.org/10.1117/12.788419 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe diamond-turned material tests for the integral field unit (IFU) for the FRIDA instrument (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias). FRIDA is closely based on the design of the successful FISICA cryogenic infrared image slicing device, which used "monolithic" mirror arrays, diamond turned into single pieces of metal. FRIDA, however, will require better roughness characteristics than the 15nm RMS of FISICA to avoid light scatter in FRIDA's shorter wavelength limit (900nm). Al 6061 seems to be limited to this roughness level by its silicate inclusions so some new combination of materials that are compatible with FRIDA's Al 6061 structure must be found. To this end, we have tested six diamond-turned mirrors with different materials and different platings. We used the Zygo interferometer facility at IA-UNAM to do warm and cold profile measurements of the mirrors to investigate possible bimetallic deformation effects. We present a detailed comparison of the various performance characteristics of the test mirrors.

Select this Article		A wide-field near-infrared camera and spectrograph for the Mt. Abu 1.2 m telescope Boddapati Anandarao, Eric Harvey Richardson, Abhijit Chakraborty, and Harland Epps Proc. SPIE 7014, 70142Y (2008); http://dx.doi.org/10.1117/12.788246 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the design and optimization of a wide-field near-infrared camera and spectrograph (NICAS) for Mt Abu 1.2 m, f/13 Cassegrain telescope of Physical Research Laboratory. The principal science goals include photometric mapping of star forming regions and medium resolution spectroscopy of Young Stellar Objects, evolved stars and transient sources. The design goals are to achieve seeing-limited angular resolution in an un-vignetted field of view of ~ 8'x8' with 0.5" per pixel (of 18.5 μm) on a HgCdTe 1024×1024 infrared array, requiring a two-fold Cassegrain focal reduction. In addition to the imaging, the instrument is required to have spectroscopic capability with a resolving power of 10³ in the 0.85 - 2.5 μm region, needing a dispersion of 1 nm per pixel. Finally, since our telescope has a moderate aperture, the throughput losses need to be minimized. The specifications are achieved by an optical design using 9 singlet lenses. Only those lens materials are chosen for which measured values are available for refractive indices at 77 K (detector operating temperature), changes of indices with temperature, and thermal coefficients of expansion. The design is optimized to give sharpest images at 77 K. The optical path is folded by 90° after collimation by a fold-mirror and re-imaged on the detector. The fold-mirror is replaced by a diffraction grating for spectrograph mode. In order to minimize the reflection losses, all the lenses will be anti-reflection coated for the full operating wavelength range. Details of the design are presented.

Select this Article		MOSFIRE: a multi-object near-infrared spectrograph and imager for the Keck Observatory Ian S. McLean, Charles C. Steidel, Keith Matthews, Harland Epps, and Sean M. Adkins Proc. SPIE 7014, 70142Z (2008); http://dx.doi.org/10.1117/12.788142 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract MOSFIRE, the multi-object spectrometer for infra-red exploration, is a near-IR (0.97-2.45 micron) spectrograph and imager for the Cassegrain focus of the Keck I telescope. The optical design provides imaging and multi-object spectroscopy over a field of view (FOV) of 6.14' x 6.14' with a resolving power of R~3,270 for a slit width of 0.7 arc seconds (2.9 pixels along dispersion). The detector is a 2.5 micron cut-off 2K x 2K H2-RG HgCdTe array with a SIDECAR ASIC for detector control. A special feature of MOSFIRE is that its multiplex advantage of up to 46 slits is achieved using a cryogenic Configurable Slit Unit (developed in collaboration with the Swiss Centre for Electronics and Micro Technology) reconfigurable under remote control in <5 minutes without thermal cycling. Slits are formed by moving opposable bars from both sides of the focal plane. An individual slit has a length of ~7.1 arc seconds but bar positions can be aligned to make longer slits. A single diffraction grating in two positions along with order-sorting filters gives essentially full coverage of the K, H, J and Y bands using 3rd, 4th, 5th or 6th order respectively. The grating and a mirror are mounted back-to-back, and when the bars are retracted from the FOV MOSFIRE becomes a wide-field imager. A piezo tip-tilt mirror following the field lens is used to provide flexure compensation at the 0.1 pixel level. Two large CCR heads allow the instrument to reach operating temperature in ~7 days. MOSFIRE is currently in construction.

Select this Article		Design options for high-performance high-resolution near-infrared spectrographs Kenneth H. Hinkle, Richard Joyce, Ming Liang, and Gary Muller Proc. SPIE 7014, 701430 (2008); http://dx.doi.org/10.1117/12.787693 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The combination of immersion grating and infrared array detector technologies now allows the construction of high-resolution spectrographs in the near-infrared that have capabilities approaching those of optical spectrographs. It is possible, for instance, to design multi-object spectrographs with very large wavelength coverage and high throughput. However, infrared spectrographs must be cryogenic and the cost of complexity can be large. We investigate lower cost design options for single-object high-resolution spectrographs. The trade-off in these designs is between the size/number of infrared arrays and the inclusion of moving parts. We present a design for a no moving parts spectrograph with either 1.1-2.5 or 3- 5 μm simultaneous wavelength coverage. The design was undertaken with attention to cost as well as scientific merit. Here we review the science drivers and key functional requirements. We present a general overview of the instrument and estimate the limiting performance. The performance is compared with that of medium-resolution infrared spectrographs as well as other high-resolution infrared spectrographs.

Select this Article		Designing the optimal semi-warm NIR spectrograph for SALT via detailed thermal analysis Marsha J. Wolf, Andrew I. Sheinis, Mark P. Mulligan, Jeffrey P. Wong, and Allen Rogers Proc. SPIE 7014, 701432 (2008); http://dx.doi.org/10.1117/12.788066 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The near infrared (NIR) upgrade to the Robert Stobie Spectrograph (RSS) on the Southern African Large Telescope (SALT), RSS/NIR, extends the spectral coverage of all modes of the optical spectrograph. The RSS/NIR is a low to medium resolution spectrograph with broadband, spectropolarimetric, and Fabry-Perot imaging capabilities. The optical and NIR arms can be used simultaneously to extend spectral coverage from 3200 Å to approximately 1.6 μm. Both arms utilize high efficiency volume phase holographic gratings via articulating gratings and cameras. The NIR camera incorporates a HAWAII-2RG detector with an Epps optical design consisting of 6 spherical elements and providing subpixel rms image sizes of 7.5 ± 1.0 μm over all wavelengths and field angles. The NIR spectrograph is semi-warm, sharing a common slit plane and partial collimator with the optical arm. A pre-dewar, cooled to below ambient temperature, houses the final NIR collimator optic, the grating/Fabry-Perot etalon, the polarizing beam splitter, and the first three camera optics. The last three camera elements, blocking filters, and detector are housed in a cryogenically cooled dewar. The semi-warm design concept has long been proposed as an economical way to extend optical instruments into the NIR, however, success has been very limited. A major portion of our design effort entails a detailed thermal analysis using non-sequential ray tracing to interactively guide the mechanical design and determine a truly realizable long wavelength cutoff over which astronomical observations will be sky-limited. In this paper we describe our thermal analysis, design concepts for the staged cooling scheme, and results to be incorporated into the overall mechanical design and baffling.

Select this Article		Warm infrared echelle spectrograph (WINERED): testing of optical components and performance evaluation of the optical system Chikako Yasui, Sohei Kondo, Yuji Ikeda, Atsushi Minami, Kentaro Motohara, and Naoto Kobayashi Proc. SPIE 7014, 701433 (2008); http://dx.doi.org/10.1117/12.788371 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We are developing a new NIR high-resolution (R_max = 100, 000) and high-sensitive spectrograph WINERED, specifically customized for short NIR bands at 0.9-1.35 μm. WINERED employs the following novel approaches in the optical system: portable design with a ZnSe immersion grating and warm optics without any cold stops. These concepts result in several essential advantages: easy to build, align, and maintain; these result in a short development time and low cost. WINERED is also equipped with a "normal echelle mode", which can cover the entire wavelength range simultaneously with R = 30, 000. In this poster paper, we will present the results of the detailed testing of optical components and the laboratory first light for the normal echelle mode. See Poster paper 7018-183 by Ikeda et al. in another session for the status of the development of the ZnSe immersion grating for R = 100, 000. We plan to complete the normal mode first by the end of 2008 and will install the immersion grating in 2010.

Select this Article		High resolution spectrograph unit (HRU) for the SUBARU/IRCS Hiroshi Terada, Ikeda Yuji, Naoto Kobayashi, Chikako Yasui, Tae-Soo Pyo, Tomonori Usuda, Masahiko Hayashi, and Hideyo Kawakita Proc. SPIE 7014, 701434 (2008); http://dx.doi.org/10.1117/12.788561 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present an upgrade plan of the infrared camera and spectrograph for the Subaru Telescope (IRCS^1-4) to introduce the high resolution spectroscopic mode (a resolving power; R=λ/Δλ > 70,000) in the infrared bands (1.4-5.5 μm). To realize the compact and stable cooled instrument, we are developing the immersion grating⁵ with Si whose refractive index is ~ 3.4. The optics design is significantly compact (600mm × 250mm × 250mm) using the Si immersion grating, and it can be easily located beside or inside the IRCS main dewar. The IRCS has been operating for 8 years with an extremely stable condition, and it is combined with the next generation adaptive optics system (AO188⁶) and the laser guide star system (LGS⁷) of the Subaru Telescope. The quick integration of the new high resolution spectrograph unit (HRU) can be expected by using the existing stable instrument. The total performance with the designed optics is so good that the optical design could meet the required specifications. The image quality shows a strehl ratio of > 0.88 for the entire bands, and 24 scannings of the gratings can cover the 1.4-5.5 μm. We plan to fabricate the Si immersion grating for the actual astronomical use in 2009, and the HRU will be built around 2011. It will be the first high sensitive infrared spectrograph with high spectral resolution capability in the northern hemisphere and with the laser guide star AO system.

Select this Article		FLEX-the first light explorer: a pathfinder instrument for fibre Bragg grating OH suppression Anthony J. Horton, Simon C. Ellis, Joss Bland-Hawthorn, Roger Haynes, and Andrew J. McGrath Proc. SPIE 7014, 701435 (2008); http://dx.doi.org/10.1117/12.788629 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present FLEX, an instrument to demonstrate the power of fibre Bragg grating OH suppression. This ground breaking technology promises great gains in sensitivity for near infrared instrumentation and the time is now right for a pioneer instrument to prove the effectiveness of the technique. Our proposal is for an adaptive optics fed integral field unit for an 8 metre class telescope. We envisage a 61 element IFU with 0.22" sampling and a 2.2" field of view. J and H-band OH suppression units would cleanly suppress the atmospheric emission lines, effectively lowering the sky background by 3 or 4 magnitudes respectively. The capabilities of FLEX will make it ideal for deep Epoch of Reionisation studies, as well as studies of star formation at z~1-4. To enable rapid and economical deployment FLEX would use an existing near infrared spectrograph with R ≈ 1000 and employ facility adaptive optics.

Select this Article		Straylight considerations for NIR spectrographs Marc Ferlet Proc. SPIE 7014, 701436 (2008); http://dx.doi.org/10.1117/12.788762 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Modern NIR spectrographs aiming at the detection and spectral study of faint deep sky objects are potentially sensitive to performances-degrading straylight effects. In particular, the following straylight mechanisms have been identified: - ghost images, inherent to large aperture broadband camera in multi-band spectrographs, have often specific distribution which can (and needs to) be simulated when baffling is not possible; - scattered light generated at the surface of the component is also interesting in the NIR spectrum as it is often at the cross-over between a micro-roughness dominated behaviour and a particulate contamination dominated one; - the use of dispersing element such as diffraction grating brings its own straylight issues related to the control of non-evanescent orders and under incidence different from the one given by the main sequential optical path from telescope to detector; - finally, thermal background from local spectrograph environment or more remote observatory-level sources affects particularly the long wavelength end of the NIR spectrum (H and K bands typically) and in-band or out-of-band rejection is desirable as complementary or even alternative to potentially complex and costly full cryogenic operation. These different points are discussed and illustrated through case studies of several NIR multi-object spectrograph designs like the fibre-fed reflective grating with OH lines suppression FMOS (designed and built), the broadband multi-IFU slicer and slit grating KMOS (under development) and the fibre-fed grism-based SIDE (in conceptual design stage).

Select this Article		ISLE: near-infrared imager/spectrograph for the 1.88m Telescope at Okayama Astrophysical Observatory Kenshi Yanagisawa, Kiichi Okita, Yasuhiro Shimizu, Masaaki Otsuka, Shogo Nagayama, Ikuru Iwata, Shinobu Ozaki, Michitoshi Yoshida, Hidehiko Nakaya, Akito Tajitsu, Shin-ichiro Okumura, and Tomoyasu Yamamuro Proc. SPIE 7014, 701437 (2008); http://dx.doi.org/10.1117/12.788905 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract ISLE is a near-infrared imager and spectrograph for the Cassegrain focus (f/18) of the 1.88 m telescope at Okayama Astrophysical Observatory. It is upgraded instrument with a new detector, HAWAII-1 HgCdTe array and new optics. ISLE provides imaging capabilities which covers 4.2 × 4.2 arcmin² field-of-view at 0.25 arc-sec/ pixel and long-slit (4 arcmin) spectroscopic capabilities at λ/Δλ = 1000 - 4000 using reflection gratings. The noise performance of the detector is excellent. The read noise of 2.5 electrons with 25 Fowler pairs has been achieved, that is one of the world's lowest level among the instruments which use HAWAII-1 array as the detector. We discuss the technical performance of ISLE and examine the upgrade effectiveness.

Select this Article		OSIRIS optical integration and tests José L. Rasilla, Roberto López López, and Carlos Tejada Proc. SPIE 7014, 701438 (2008); http://dx.doi.org/10.1117/12.789093 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS) is the first light instrument for the 10.4 meters Gran Telescopio de Canarias (GTC). It's a 8.5 × 8.5 arc-min visible camera; a set of grisms provides low resolution spectroscopic capability. In this contribution the accessories and mountings for alignment are presented as well as the techniques used. Also, a complete characterization of the system at laboratory for image quality, spectral and spatial resolution, and image movement, etc. are shown.

Select this Article		Control system for the AMICA infrared camera F. Bortoletto, D. Magrin, C. Bonoli, M. D'Alessandro, D. Fantinel, G. Di Rico, C. Giuliani, A. di Cianno, and L. Corcione Proc. SPIE 7014, 70143A (2008); http://dx.doi.org/10.1117/12.789086 \| Cited 2 times Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract AMICA (Antarctic Medium Infrared Camera) [1] is the imaging camera that will support first-light testing for the IRAIT telescope. IRAIT (International Robotic Antarctic Infrared Telescope) is a 80 cm class telescope to be installed at Dome C, a site located at 3200m height on the Antarctic plateau. AMICA, placed at the telescope Nasmyth focus, is a dual feed infrared camera: a medium infrared optical beam designed to be operated by a Si:As detector array covering the range 5-28 μm, and a near infrared optical beam operated by a In:Sb detector array covering the spectral range down to J band. A specific goal of this project, having to face the prohibitive Antarctic environment imposing strong limits to human and equipments operation, is the need to implement robotic and remotely controlled procedures for the telescope and its instrumentation. This will impose well integrated and cooperative control systems, besides the accurate insulation for all the equipment exposed to the extreme environmental conditions of Dome C (T -90, p 640 mbar). In the present paper we will provide an overview of the progress so far obtained in the construction and testing of the AMICA control system.

Select this Article		Detector upgrade for FLAMES: GIRAFFE gets red eyes Claudio Melo, Mark Downing, Paul Jorden, Luca Pasquini, Sebastian Deiries, Andrew Kelt, Dominique Naef, Reinhard Hanuschik, Ralf Palsa, Roberto Castillo, Eduardo Peña, Eduardo Bendek, and Mark Gieles Proc. SPIE 7014, 70143B (2008); http://dx.doi.org/10.1117/12.789092 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract GIRAFFE is an intermediate resolution spectrograph covering a wavelength range from 360-930nm and fed by optical fibers as a part of FLAMES, the multi-object fiber facility mounted at the ESO VLT Kueyen. For some time we sought a new detector for GIRAFFE spectrograph to boost the instrument's red QE (Quantum Efficiency) capabilities, while still retaining very good blue response. We aimed also at reducing the strong fringing present in the red spectra. The adopted solution was an e2v custom 2-layer AR (Anti-Reflection) coated Deep Depletion CCD44-82 CCD. This device was made in a new e2v Technologies AR coating plant and delivered to ESO in mid 2007 with performance that matches predictions. The new CCD was commissioned in May 2008. Here we report on the results.

Select this Article		Characterization and testing of FLAMINGOS-2: the Gemini facility near-infrared multi-object spectrometer and wide-field imager Steven N. Raines, Stephen S. Eikenberry, Reba M. Bandyopadhyay, Jeffrey A. Julian, Kevin T. Hanna, Craig D. Warner, Roger E. Julian, J. Greg Bennett, Curtis N. DeWitt, Skip Frommeyer, Anthony Gonzalez, Michael D. Herlevich, and Charles Murphey Proc. SPIE 7014, 70143C (2008); http://dx.doi.org/10.1117/12.789271 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FLAMINGOS-2 is a near-infrared wide-field imager and fully cryogenic multi-object spectrometer for Gemini Observatory being built by the University of Florida. FLAMINGOS-2 can simultaneously carry 9 custom cryogenic multi-object slit masks exchangeable without thermally cycling the entire instrument. Three selectable grisms provide resolving powers which are ~1300 to ~3000 over the entire spectrograph bandpass of 0.9-2.5 microns. We present and discuss characterization data for FLAMINGOS-2 including imaging throughput, image quality, spectral performance, and noise performance. After a lengthy integration process, we expect that FLAMINGOS-2 will be in the midst of commissioning at Gemini South by the fall of 2008.

Select this Article		SPHERE IFS: the spectro differential imager of the VLT for exoplanets search R. U. Claudi, M. Turatto, R. G. Gratton, J. Antichi, M. Bonavita, P. Bruno, E. Cascone, V. De Caprio, S. Desidera, E. Giro, D. Mesa, S. Scuderi, K. Dohlen, J. L. Beuzit, and P. Puget Proc. SPIE 7014, 70143E (2008); http://dx.doi.org/10.1117/12.788366 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract SPHERE is an exo-solar planet imager, which goal is to detect giant exo-solar planets in the vicinity of bright stars and to characterize them through spectroscopic and polarimetric observations. It is a complete system with a core made of an extreme-Adaptive Optics (AO) turbulence correction, pupil tracker and interferential coronagraphs. At its back end, a differential dual imaging camera and an integral field spectrograph (IFS) work in the Near Infrared (NIR) Y, J, H and Ks bands (0.95 - 2.32μm) and a high resolution polarization camera covers the visible (0.6 - 0.9 μm). The IFS is a low resolution spectrograph (R~50 and R~30) which works in the near IR (0.95-1.7 microns), an ideal wavelength range for the detection of planetary features. In our baseline design the IFU is a new philosophy microlens array of about 145x145 elements designed to reduce as low as possible the contrast. The IFU will cover a field of view of about 1.8 x 1.8 square arcsecs reaching a contrast of 10^-7, giving an high contrast and high spatial resolution "imager" able to search for planet well inside the star PSF.

Select this Article		SPHERE ZIMPOL: overview and performance simulation Christian Thalmann, Hans M. Schmid, Anthony Boccaletti, David Mouillet, Kjetil Dohlen, Ronald Roelfsema, Marcel Carbillet, Daniel Gisler, Jean-Luc Beuzit, Markus Feldt, Raffaele Gratton, Franco Joos, Christoph U. Keller, Jan Kragt II, Johan H. Pragt, et al. Proc. SPIE 7014, 70143F (2008); http://dx.doi.org/10.1117/12.789158 \| Cited 2 times Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The ESO planet finder instrument SPHERE will search for the polarimetric signature of the reflected light from extrasolar planets, using a VLT telescope, an extreme AO system (SAXO), a stellar coronagraph, and an imaging polarimeter (ZIMPOL). We present the design concept of the ZIMPOL instrument, a single-beam polarimeter that achieves very high polarimetric accuracy using fast polarization modulation and demodulating CCD detectors. Furthermore, we describe comprehensive performance simulations made with the CAOS problem-solving environment. We conclude that direct detection of Jupiter-sized planets in close orbit around the brightest nearby stars is achievable with imaging polarimetry, signal-switching calibration, and angular differential imaging.

Select this Article		SPHERE-IFS arm: a new concept of Nasmyth II generation instrumentation for ESO-VLT V. De Caprio, P. Bruno, E. Cascone, S. Scuderi, R. Claudi, R. G. Gratton, E. Giro, J. Antichi, S. Desidera, M. Tintori, D. Mesa, E. Stadler, M. Turatto, and J. L. Beuzit Proc. SPIE 7014, 70143G (2008); http://dx.doi.org/10.1117/12.789420 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Direct detection and spectral characterization of Extrasolar Planets is one of the most exciting but also one of the most challenging areas in modern astronomy. For the second-generation instrumentation on the VLT, ESO has supported the study and the design of instrument, called SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research). SPHERE includes a powerful extreme adaptive optics system, various coronagraphs, an infrared differential imaging camera (IRDIS), an infrared Integral Field Spectrograph (IFS) and a visible differential polarimeter (ZIMPOL). IFS is a very low resolution spectrograph (R~50) which works in the near IR (0.95-1.7 microns), an ideal wavelength range for the ground based detection of planetary features. The IFS requirements have been met via an innovative integrated design merging passive stiffness and active control to obtain a light, accessible and functional assembly. This paper gives a description of its cryogenic and mechatronic integrated design.

Select this Article		SPHERE IFS optical concept description and design overview J. Antichi, R. G. Gratton, R. U. Claudi, E. Giro, D. Mesa, S. Desidera, S. Scuderi, P. Bruno, M. Turatto, E. Cascone, V. De Caprio, J.-L. Beuzit, P. Puget, and K. Dohlen Proc. SPIE 7014, 70143H (2008); http://dx.doi.org/10.1117/12.789245 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Integral field spectroscopy coupled with an extreme adaptive optics system and coronagraphy allows a marked improvement of the standard spectroscopic simultaneous differential imaging calibration technique. Hence, with an integral field spectrograph (IFS) direct imaging of extrasolar giant planets becomes potentially feasible over a wide range of ages, masses, and separations from the hosting stars. This aim represents the prime goal of the planet finder instrument for the VLT (SPHERE). Inside SPHERE, the IFS channel exploits various spectral features of the candidate planets in the near infrared, in order to reduce the speckles noise at the level of the stellar background noise, over a field of view comprised between the coronagraphic inner working angle and the outer working angle provided by the SPHERE extreme adaptive optic system (SAXO). The IFS allows then to realize an extensive spectroscopic simultaneous differential imaging calibration technique, and at least in few cases, to get the spectrum of the candidate extrasolar giant planets. Here we present the IFS baseline design, which is based upon a new optical concept we developed for its integral field unit (BIGRE). When applied to the technical specifications of SPHERE IFS, a BIGRE integral field unit is able to take into account all the effects appearing when integral field spectroscopy is used in diffraction limited conditions and for high-contrast imaging purposes. Finally a BIGRE-oriented IFS optical design is shown here to reach the requested high optical quality by standard lenses-based optical devices.

Select this Article		Frame combination techniques for ultra-high-contrast imaging Joseph C. Carson, Markus Feldt, Silvano Desidera, Maud Langlois, Franco Joos, David Mouillet, and Jean-Luc Beuzit Proc. SPIE 7014, 70143I (2008); http://dx.doi.org/10.1117/12.789172 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We summarize here an experimental frame combination pipeline we developed for ultra high-contrast imaging with systems like the upcoming VLT SPHERE instrument. The pipeline combines strategies from the Drizzle technique, the Spitzer IRACproc package, and homegrown codes, to combine image sets that may include a rotating field of view and arbitrary shifts between frames. The pipeline is meant to be robust at dealing with data that may contain non-ideal effects like sub-pixel pointing errors, missing data points, non-symmetrical noise sources, arbitrary geometric distortions, and rapidly changing point spread functions. We summarize in this document individual steps and strategies, as well as results from preliminary tests and simulations.

Select this Article		Apodized Lyot coronagraph for VLT-SPHERE: laboratory tests and performances of a first prototype in the visible Géraldine Guerri, Sylvie Robbe-Dubois, Jean-Baptiste Daban, Lyu Abe, Richard Douet, Philippe Bendjoya, Farrokh Vakili, Marcel Carbillet, Jean-Luc Beuzit, Pascal Puget, Kjetil Dohlen, and David Mouillet Proc. SPIE 7014, 70143J (2008); http://dx.doi.org/10.1117/12.789688 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present some of the High Dynamic Range Imaging activities developed around the coronagraphic test-bench of the Laboratoire A. H. Fizeau (Nice). They concern research and development of an Apodized Lyot Coronagraph (ALC) for the VLT-SPHERE instrument and experimental results from our testbed working in the visible domain. We determined by numerical simulations the specifications of the apodizing filter and searched the best technological process to manufacture it. We present the results of the experimental tests on the first apodizer prototype in the visible and the resulting ALC nulling performances. The tests concern particularly the apodizer characterization (average transmission radial profile, global reflectivity and transmittivity in the visible), ALC nulling performances compared with expectations, sensitivity of the ALC performances to misalignments of its components.

Select this Article		BIGRE: a new double microlens array for the integral field spectrograph of SPHERE E. Giro, R. U. Claudi, J. Antichi, P. Bruno, E. Cascone, V. De Caprio, S. Desidera, R. G. Gratton, D. Mesa, S. Scuderi, M. Turatto, J. L. Beuzit, K. Dohlen, and P. Puget Proc. SPIE 7014, 70143K (2008); http://dx.doi.org/10.1117/12.789354 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract IFS is the Integral Field Spectrograph for SPHERE, a 2nd generation instrument for VLT devoted to the search of exoplanets. To achieve the performances required for the IFS a new device sampling the focal plane has been designed, prototyped and tested in laboratory. This device named BIGRE consists of a system made of two microlens arrays with different focal lengths and thickness equal to the sum of them and precisely aligned each other. Moreover a mask has been deposited on the first array to produce a field stop for each lenslet. Laboratory tests confirmed that specifications and properties of the prototype are met by state of the art on optics microlens manufacturing. To characterize the device, a simulator of IFS has been built in laboratory and the BIGRE properties have been tested in real working conditions, showing that the design of the double array fulfills IFS requirements.

Select this Article		The infra-red dual imaging and spectrograph for SPHERE: design and performance Kjetil Dohlen, Maud Langlois, Michel Saisse, Lucien Hill, Alain Origne, Marc Jacquet, Christophe Fabron, Jean-Claude Blanc, Marc Llored, Michael Carle, Claire Moutou, Arthur Vigan, Anthony Boccaletti, Marcel Carbillet, David Mouillet, et al. Proc. SPIE 7014, 70143L (2008); http://dx.doi.org/10.1117/12.789786 \| Cited 3 times Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research) planet finder instrument for ESO's VLT telescope, scheduled for first light in 2011, aims to detect giant extra-solar planets in the vicinity of bright stars by the aid of an extreme-AO turbulence compensation system and to characterize the objects found through spectroscopic and polarimetric observations. Dual imaging observations within the Y, J, H and Ks atmospheric windows (~0.95 - 2.32μm) will be done by the aid of the IRDIS cryogenic camera. We describe briefly the science goals of IRDIS and present its system architecture. Current status of the instrument design is presented, and expected performance is described in terms of end-to-end simulations.

Select this Article		Calibration and data reduction for planet detection with SPHERE-IFS S. Desidera, R. Gratton, R. Claudi, J. Antichi, D. Mesa, M. Turatto, P. Bruno, E. Cascone, V. De Caprio, E. Giro, S. Scuderi, M. Feldt, A. Pavlov, O. Moeller-Nilsson, K. Dohlen, et al. Proc. SPIE 7014, 70143M (2008); http://dx.doi.org/10.1117/12.789153 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The 2nd generation VLT instrument SPHERE will include an integral field spectrograph to enhance the capabilities of detection of planetary companions close to bright stars. SPHERE-IFS is foreseen to work in near IR (0.95-1.65 micron) at low spectral resolution. This paper describes the observing strategies, the adopted hardware solutions for calibrating the instrument, and the data reduction procedures that are mandatory for the achievement of the extreme contrast performances for which the instrument is designed.

Select this Article		High efficiency near infrared spectrometer for zodiacal light spectral study A. S. Kutyrev, R. Arendt, E. Dwek, S. H. Moseley, D. Rapchun, and R. F. Silverberg Proc. SPIE 7014, 70143N (2008); http://dx.doi.org/10.1117/12.790184 Online Publication Date: Jul 14, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We are developing a near infrared spectrometer for measuring solar absorption lines in the zodiacal light in the near infrared region. it has been recently demonstrated¹ that observing single Fraunhofer line can be a powerful tool for extracting zodiacal light parameters based on the measurements of the profile of the Mg I line at 5184 A. We are extending this technique to the near infrared with the primary goal of measuring the absolute intensity of the zodiacal light. This measurement will provide the crucial information needed to accurately subtract zodiacal emission from the DIRBE (Diffuse Infrared Background Experiment) diffuse sky measurements to determine the intensity of the extragalactic infrared background. The instrument design is based on a dual Fabry-Perot interferometer with a narrow band filter. Its double etalon design allows to achieve high spectral contrast to reject the bright out of band atmospheric hydroxyl emission. High spectral contrast is absolutely necessary to achieve detection limits needed to accurately measure the intensity of the absorption line. We present the design, the estimated performance of the instrument, and the expected results of the observing program.

Select this Article		KMOS housekeeping electronics and its functions Nagaraja Bezawada, Brian Woodward, and Phil Rees Proc. SPIE 7014, 70143P (2008); http://dx.doi.org/10.1117/12.790389 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract KMOS is a second generation near infrared multi-object spectrograph instrument for the VLT. It is a highly complex astronomical instrument with over 60 cryo-mechanisms deploying pickoff arms, moving filter wheels and detector focus stages. The instrument houses three identical sections each consisting of 8 pickoff arms, 2 filter wheels, 8 integral field units feeding a spectrograph and its detector systems. The housekeeping electronics provides a semi-automation of the cryostat functions such as pump down, cool down and warm up sequences, vacuum and temperature measurement and control etc. The infrastructure electronics is responsible for the safe operation of the instrument. It monitors the various cryostat conditions, takes automatic corrective actions under faulty conditions and raises alarms when a manual intervention is needed. This semi-automation design is aimed at not only minimising the risk of instrument damage, but also takes into account the safety of instrument manual handling. This paper describes the design of the instrument infrastructure electronics and details its functions such as semi-automation of the cryostat procedures, housekeeping diagnostics, automatic corrective actions under faulty conditions, scheme of alarm and warnings, detector thermal protection etc. and presents the associated interfaces to the control electronics and the cable co-rotator.

Select this Article		Airborne measurements in the longwave infrared using an imaging hyperspectral sensor Jean-Pierre Allard, Martin Chamberland, Vincent Farley, Frédérick Marcotte, Matthias Rolland, Alexandre Vallières, and André Villemaire Proc. SPIE 7014, 70143Q (2008); http://dx.doi.org/10.1117/12.788027 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Emerging applications in Defense and Security require sensors with state-of-the-art sensitivity and capabilities. Among these sensors, the imaging spectrometer is an instrument yielding a large amount of rich information about the measured scene. Standoff detection, identification and quantification of chemicals in the gaseous state is one important application. Analysis of the surface emissivity as a means to classify ground properties and usage is another one. Imaging spectrometers have unmatched capabilities to meet the requirements of these applications. Telops has developed the FIRST, a LWIR hyperspectral imager. The FIRST is based on the Fourier Transform technology yielding high spectral resolution and enabling high accuracy radiometric calibration. The FIRST, a man portable sensor, provides datacubes of up to 320×256 pixels at 0.35mrad spatial resolution over the 8-12 μm spectral range at spectral resolutions of up to 0.25cm^-1. The FIRST has been used in several field campaigns, including the demonstration of standoff chemical agent detection [http://dx.doi.org/10.1117/12.788027.1]. More recently, an airborne system integrating the FIRST has been developed to provide airborne hyperspectral measurement capabilities. The airborne system and its capabilities are presented in this paper. The FIRST sensor modularity enables operation in various configurations such as tripod-mounted and airborne. In the airborne configuration, the FIRST can be operated in push-broom mode, or in staring mode with image motion compensation. This paper focuses on the airborne operation of the FIRST sensor.

Select this Article		AAOmicron: a wide-field near-infrared multi-object spectrograph concept for the AAT Roger Haynes, Simon Ellis, Peter Gillingham, Anthony Horton, William Rambold, and Greg Smith Proc. SPIE 7014, 70143R (2008); http://dx.doi.org/10.1117/12.788650 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract AAOmicron is a wide-field, fiber-fed, multi-object, near-infrared spectrograph concept for the Anglo Australian Telescope (AAT). It is one of a number of instruments concepts (primarily for bright time use) recently considered to complement the existing instrumentation and in particular the highly popular AAOmega system (primarily dark and grey time usage). AAOmicron has a two-degree field of view, 240 robotically configured fibers and operates between 0.98 and 1.75μm at a resolution of R~3500. AAOmicron offers a broad suite of applications from the study of low-mass stars, to determining the structure of the high-redshift Universe. We present an overview of the instrument concept, which is based heavily on the highly successful AAOmega system, and describe how the AAOmega spectrograph design could be adapted for near-infrared observations to provide a highly cost effective and scientifically compelling instrument.

Select this Article		LUCIFER status report: summer 2008 Holger Mandel, Walter Seifert, Reiner Hofmann, Marcus Jütte, Rainer Lenzen, Nancy Ageorges, Dominik Bomans, Peter Buschkamp, Ralf-Jürgen Dettmar, Carmen Feiz, Hans Gemperlein, André Germeroth, Lutz Geuer, Jochen Heidt, Volker Knierim, et al. Proc. SPIE 7014, 70143S (2008); http://dx.doi.org/10.1117/12.787203 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract LUCIFER is a NIR spectrograph and imager (wavelength range 0.9 to 2.5 micron) for the Large Binocular Telescope (LBT) on Mt. Graham, Arizona, working at cryogenic temperatures of less than 70K. Two instruments are built by a consortium of five German institutes and will be mounted at the bent Gregorian foci of the two individual telescope mirrors. Three exchangable cameras are available for imaging and spectroscopy: two of them are optimized for seeing-limited conditions, a third camera for the diffraction limited case will be used with the LBT adaptive secondary mirror working. Up to 33 exchangeable masks are available for longslit or multi-object spectroscopy (MOS) over the full field of view (FOV). Both MOS-units (LUCIFER 1 and LUCIFER 2) and the auxiliary cryostats together with the control electronics have been completed. The observational software-package is in its final stage of preparation. After the total integration of LUCIFER 1 extensive tests were done for all electro-mechanical functions and the verification of the instrument started. The results of the tests are presented in detail and are compared with the specifications.

Select this Article		Performances of the cryogenic system of GIANO-TNG I. Mochi, E. Oliva, L. Origlia, C. Baffa, V. Biliotti, G. Falcini, E. Giani, M. Gonzalez, E. Rossetti, M. Sozzi, M. Liffredo, G. Roveta, and L. Roccia Proc. SPIE 7014, 70143U (2008); http://dx.doi.org/10.1117/12.788241 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract GIANO-TNG is a cryogenic high resolution infrared spectrometer whose optics include large aspheric mirrors and cross-dispersing prisms mounted over a ≃1.5 m² aluminum bench. To achieve the highest possible spectral stability and repeatability the bench is internally filled with liquid nitrogen whose boil-off pressure is actively controlled and stabilized to a fraction of mbar. The bench is isostatically mounted inside a ≃2.5 m³ cryostat. We present the characteristics and performances of the cryogenic system of GIANO which include, in particular, a temperature uniformity and long-term stability of a few mK and a remarkably low consumption of liquid nitrogen (less than 1 liter/hr).

Select this Article		Characterization of the HCl-HBr-HI gas absorption cell for GIANO-TNG Francesco D'Amato, Silvia Viciani, Ernesto Oliva, Livia Origlia, and Iacopo Mochi Proc. SPIE 7014, 70143V (2008); http://dx.doi.org/10.1117/12.788231 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract GIANO is an high resolution cross-dispersed spectrometer operating at near IR wavelengths (0.9-2.5 microns) which will be soon commissioned at the 3.6m TNG Italian telescope in La Palma. One of its most ambitious aims is searching for earth-like planets with habitable conditions around very cool main sequence stars. This requires measurements of radial velocities with accuracies of a few m/s which can be achieved by means of a gas absorption cell containing a mixture of the halogen-hydrates HCl, HBr and HI. We present here the results of the laboratory work for the construction and characterization of such cell.

Select this Article		Integration, commissioning, and performance of the UK FMOS spectrograph Gavin B. Dalton, Ian J. Lewis, Ian A. J. Tosh, Colin Blackburn, David G. Bonfield, Charles B. Brooks, Alan R. Holmes, Hanshin Lee, Tim R. Froud, Masayuki Akiyama, Naoyuki Tamura, and Naruhisa Takato Proc. SPIE 7014, 70143W (2008); http://dx.doi.org/10.1117/12.787619 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The UK FMOS spectrograph forms part of Subaru's FMOS multi-object infrared spectroscopy facility. The spectrograph was shipped to Hilo in component form in August of 2007. We describe the integration sequence for the spectrograph, the results of cooldown tests using a new chiller unit fitted to the spectrograph at the telescope, and alignment tests of the spectrograph, gratings and OH-suppression masks. We present the first-light observations for the spectrograph from May 2008.

Select this Article		X-shooter physical model Paul Bristow, Florian Kerber, Michael R. Rosa, Joel Vernet, Paolo Goldoni, Paolo Spanò, and Andrea Modigliani Proc. SPIE 7014, 70143X (2008); http://dx.doi.org/10.1117/12.789085 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have developed a physical model of the VLT 2nd generation instrument X-shooter for use in wavelength calibration. We describe here the model concept, its use during the development of the data reduction software and the initial alignment of the spectrograph in the laboratory and the optimisation of the model to fit early laboratory data.

Select this Article		Wavelength calibration sources for the near infrared arm of X-shooter Florian Kerber, Francesco Saitta, Paul Bristow, and Joel Vernet Proc. SPIE 7014, 70143Y (2008); http://dx.doi.org/10.1117/12.787299 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have studied the properties of wavelength calibration sources for the near-IR (NIR: 1000-2500 nm) arm of X-shooter. In a novel approach we are combining laboratory measurements from a Fourier Transform Spectrometer (FTS) and literature data with corresponding simulated data derived from a physical model of X-shooter. The sources studied are pen ray lamps filled with the noble gases Ne, Ar, Kr, and Xe and Th-Ar hollow cathode lamps. As a product we provide a quantitative order by order analysis of the expected properties of the calibration lamps during X-shooter operations. The analysis accounts for blending of lines and makes realistic assumptions about the dynamic range available in a typical wavelength calibration exposure. Based on our study we recommend the use of Ne, Kr, and Ar as the best three lamp combination for X-shooter calibration. A detailed comparison between the predicted and actual performance of the calibration system has been started as part of the X-shooter testing and validation phase and first results are very promising. To our knowledge this is the first time that such a detailed and quantitative analysis of a calibration system has been done prior to the operation of the instrument. The combination of laboratory measurements and instrument modeling provides a powerful tool for future instrument development.

Select this Article		X-shooter-backbone and UV-blue and visible spectrographs: final AIV and measured performances Per Kjærgaard Rasmussen, Filippo M. Zerbi, Hans Dekker, Joel Vernet, Jeppe J. Andersen, Vincenzo De Caprio, Paolo Dimarcantonio, Sandro D'Odorico, Jean-Louis Lizon, Christian Lucuix, Niels Michaelsen, Emilio Molinari, Preben Nørregaard, Alberto Riva, Marco Riva, et al. Proc. SPIE 7014, 70143Z (2008); http://dx.doi.org/10.1117/12.788745 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract X-shooter is a wide band (U to K) intermediate resolution (4000-14000) single object three-arms spectrograph for the VLT. Currently in the last phase of integration, X-shooter will see the first light at ESO Paranal as the first of the VLT second generation instruments in the last quarter of 2008. We describe in this paper the final steps in the integration and testing phase of the central Backbone with its key functions (including the active flexure compensation mirrors) and of the two UV-Blue and Visible spectroscopic arms. We report on the stability results of the preslit optics and of the spectrographs and on the remarkable efficiency which is derived from the measurements of the optical components of the instrument.

Select this Article		A new measurement method of profile tolerance for the LAMOST focal plane Zengxiang Zhou, Yi Jin, Chao Zhai, and Xiaozheng Xing Proc. SPIE 7014, 701440 (2008); http://dx.doi.org/10.1117/12.787054 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract There were a few methods taken in the profile tolerance measurement of the LAMOST Focal Plane Plate. One of the methods was to use CMM (Coordinate Measurement Machine) to measure the points on the small Focal Plane Plate and calculate the points whether or not in the tolerance zone. In this process there are some small shortcomings. The measuring point positions on the Focal Plane Plate are not the actual installation location of the optical fiber positioning system. In order to eliminate these principle errors, a measuring mandrel is inserted into the unit-holes, and the precision for the mandrel with the hole is controlled in the high level. Then measure the center of the precise target ball which is placed on the measuring mandrel by CMM. At last, fit a sphere surface with the measuring center points of the target ball and analyze the profile tolerance of the Focal Plane Plate. This process will be more in line with the actual installation location of the optical fiber positioning system. When use this method to judge the profile tolerance can provide the reference date for maintaining the ultra error unit-holes on the Focal Plane Plate. But when insert the measuring mandrel into the unit hole, there are manufacturing errors in the measuring mandrel, target ball and assembly errors. All these errors will bring the influence in the measurement. In the paper, an impact evaluation assesses the intermediate process with all these errors through experiments. And the experiment results show that there are little influence when use the target ball and the measuring mandrel in the measurement of the profile tolerance. Instead, there are more advantages than many past use of measuring methods.

Select this Article		Study on measurement error of fiber space coordinate detection using an area CCD camera for the LAMOST positioning system Yi Jin, Xiaozheng Xing, Chao Zhai, and Zengxiang Zhou Proc. SPIE 7014, 701441 (2008); http://dx.doi.org/10.1117/12.787060 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract An area CCD camera is used to detect space coordinates of fibers in LAMOST positioning system, which is National Ninth Five Great Scientific Project, in order to achieve the detection of real-time, un-touched and high accuracy. This measurement method is based on photogrammetry and is applied in many other photometric measurement systems. The positioning accuracy for LAMOST is less than 40m, so fibers' position detection accuracy is at least one-third of it. The position detection of static goals through general photogrammetry can achieve high accuracy, about several microns. But fibers are active in LAMOST, so the systematic research about CCD measurement under this circumstance is carried on in this paper, which includes measurement error magnitude, form of expression, influencing factors, causes and ways to reduce measurement error. Some conclusions can be obtained through position detection experiments for movement fibers: The measurement method with a CCD camera for position detection has a good measurement stability, its accuracy can achieve about 2 microns for 8 hours; This method also has a high accuracy for position detection of one-dimensional movement fibers, which is less than 5 microns within the movement distance of several millimeters; But when fibers move in a curtain space freely, F number, lamp-house, speckle status and imaging size will probably cause additional measurement error. It is about a dozen microns to tens of microns and it stems from the changes of light intensity distribution of imaging speckles while fibers are moving. Finally, it is discussed simply to improve the measurement method and reduce measurement error.

Select this Article		The testing scheme for the LAMOST focal plane plate Zengxiang Zhou, Yi Jin, Jianping Wang, Xiaofeng Li, and Xiaozheng Xing Proc. SPIE 7014, 701442 (2008); http://dx.doi.org/10.1117/12.787078 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract At present, the LAMOST project is in a crucial period. The machining progressing of LAMOST Focal Plane Plate has completed. The inspection of the machining quality for the Focal Plane Plate in the machining process is a pivotal work. In all of the design requirements, the most crucial standards of accuracy are the profile tolerance and the unit-holes dimensional angle. Theirs precision will influence the observation efficiency of the LAMOST. But there are more than 4000 unit-holes on the 1.75m diameter Focal Plane Plate, it is impossible to measure all unit-holes and the whole area of the Focal Plane Plate. How to measure the minimal unit-hole and get the most accurate results about the machining process, judge whether the final machining Focal Plane Plate satisfy the design requirements. The measurement scheme optimization is discussed in the paper. There are two different ways to measure the Focal Plane Plate, one is the traditional way whish use specially designed implements for the every individual parameter, the other way used the CMM to measure the pivotal design requirements such as unit-hole dimensional angle and the profile tolerance of the Focal Plane Plate. The advantage of this is saving the time and cost on the CMM, improving the efficiency for the whole measurement work, and acquires the direct vision results before measuring the Focal Plane Plate on CMM. Whereas the implement which used in the measurement need to design and machine precisely for the credible measurement results. And all the measuring work is calibrated by the CMM sampling detection. The sampling detection based on the processing technology and some implements are mentioned in the paper.

Select this Article		Flat field for LAMOST Haotong Zhang and Zhongrui Bai Proc. SPIE 7014, 701443 (2008); http://dx.doi.org/10.1117/12.787394 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Large sky area multi-object spectroscopic telescope(LAMOST) is a reflecting schmidt telescope, the unique telescope structure make it compatible with both large sky area and large aperture. While the vignetting effect of the telescope is not the same everywhere, the flat field is quite different from the common flat field which use a lamp projecting to a fixed white screen. We describe the Schmidt reflector(MA) cover solution of the LAMOST flat field, simulation shows the variation across the field of view is less than 2 percent. The material of flat field screen is carefully chosen to have both high reflectivity and diffusion. We also describe the material test for the LAMOST flat field screen. Flat field lamp should have high color temperature to raise the sinal in the shorter wavelength. The possible solution for the flat field lamp is described.

Select this Article		A new method for measuring the position of the end of optical fibers for LAMOST Yonggang Gu, Chao Zhai, Xiaozheng Xing, and Jiaru Chu Proc. SPIE 7014, 701444 (2008); http://dx.doi.org/10.1117/12.788550 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Measuring the position of the end of 4000 optical fibers on the spherical focal plate for the LAMOST (Large Sky Area Multi-Object Fiber Spectroscopy Telescope) optical fibers positioning system is one of the key problems for LAMOST. Currently, the area CCD camera is used to measure the positions conveniently and quickly. However, due to too small size of area CCD, the large-size focal plate should be reduced large multiples to image on the area CCD, and in this process, there is error amplification which will disturb the improvement of measuring precision. So far, the precision of this method does not meet the requirement. Therefore, a new method with linear CCD sensors is created. The device consists of a rotary encoder and a scanning frame on which several linear CCD sensors are spliced into a measuring baseline. The scanning frame can be driven by step motor and take a slow rotation around the center axis of the focal plate and close to the surface of the focal plate. In the course of rotation, each time the scanning frame turns a very small angle, the linear CCD sensors take an acquisition and get the radial coordinate of the end of optical fibers, the rotary encoder records the angle coordinate, and this polar coordinates can be used to express the position of the end of optical fibers. This new method is a 1:1 measurement, and it hasn't error amplification but has high precision in theory. The main content of this paper is to build the measuring model of the new method with linear CCD.

Select this Article		MicroLux: high-precision timing of high-speed photometric observations Felix Hormuth Proc. SPIE 7014, 701446 (2008); http://dx.doi.org/10.1117/12.787328 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract MicroLux is a GPS-based high precision and high speed timing add-on to the Calar Alto Lucky Imaging camera AstraLux. It allows timestamping of individual CCD exposures at frame rates of more than 1 kHz with an accuracy better than one microsecond with respect to the UTC timeframe. The system was successfully used for high speed observations of the optical pulse profile of the Crab pulsar in January and November 2007. I present the technical design concept of MicroLux as well as first results from these observations, in particular the reconstructed pulse profile of the pulsar.

Select this Article		FastCam: a new lucky imaging instrument for medium-sized telescopes Alejandro Oscoz, Rafael Rebolo, Roberto López, Antonio Pérez-Garrido, Jorge Andrés Pérez, Sergi Hildebrandt, Luis Fernando Rodríguez, Juan José Piqueras, Isidro Villó, José Miguel González, Rafael Barrena, Gabriel Gómez, Anibal García, Pilar Montañés, Alfred Rosenberg, et al. Proc. SPIE 7014, 701447 (2008); http://dx.doi.org/10.1117/12.788834 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FastCam is an instrument jointly developed by the Spanish Instituto de Astrofsica de Canarias and the Universidad Politcnica de Cartagena designed to obtain high spatial resolution images in the optical wavelength range from ground-based telescopes. The instrument consists of a very low noise and very fast readout speed EMCCD camera capable of reaching the diffraction limit of medium-sized telescopes from 500 to 850 nm. FastCam incorporates a FPGAs-based device to save and evaluate those images minimally disturbed by atmospheric turbulence in real time. The undisturbed images represent a small fraction of the observations. Therefore, a special software package has been developed to extract, from cubes of tens of thousands of images, those with better quality than a given level. This is done in parallel with the data acquisition at the telescope. After the first tests in the laboratory, FastCam has been successfully tested in three telescopes: the 1.52-meter TCS (Teide Observatory), the 2.5-meter NOT, and the 4.2-meter WHT (Roque de los Muchachos Observatory). The theoretical diffraction limit of each telescope has been reached in the I band (850 nm) -0.15, 0.08 and 0.05 arcsec, respectively-, and similar resolutions have been also obtained in the V and R bands. Future work will include the development of a new instrument for the 10.4-meter GTC telescope on La Palma.

Select this Article		AstraLux: the Calar Alto lucky imaging camera Felix Hormuth, Stefan Hippler, Wolfgang Brandner, Karl Wagner, and Thomas Henning Proc. SPIE 7014, 701448 (2008); http://dx.doi.org/10.1117/12.787384 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract AstraLux is the Lucky Imaging camera for the Calar Alto 2.2-m telescope, based on an electron-multiplying high speed CCD. By selecting only the best 1-10% of several thousand short exposure frames, AstraLux provides nearly diffraction limited imaging capabilities in the SDSS i' and z' filters over a field of view of 24×24 arcseconds. By choosing commercially available components wherever possible, the instrument could be built in short time and at comparably low cost. We present the instrument design, the data reduction pipeline, and summarise the performance and characteristics.

Select this Article		Real-time lucky imaging in FastCam project L. F. Rodríguez Ramos, J. J. Piqueras Meseguer, Y. Martin Hernando, A. Oscoz, and R. Rebolo Proc. SPIE 7014, 701449 (2008); http://dx.doi.org/10.1117/12.787403 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Lucky imaging techniques implemented by the FastCam group (see http://www.iac.es/proyecto/fastcam/) at the Instituto de Astrofisica de Canarias have demonstrated its ability to obtain spectacular diffraction limited images in telescopes ranging from 1 to 4.2 m in visible wavelengths (mainly in the I band), at the expense of using only a small percentage of the available images. This work presents the development of a real-time processor, FPGA-based, capable of performing all the required processing involved in the lucky imaging technique: Bias and flat-field correction, quality evaluation of images, quality threshold for image selection, image recentering and accumulation, and finally sending through Gigabit Ethernet both raw and processed images to a PC computer. Furthermore, a real time display is generated directly from FPGA showing both types of images, plus a histogram of the computed quality values and the threshold used. All processes can co-exist physically located in separated places inside the FPGA, using its natural parallel approach, and can easily handle the 512x512 pixels at 30 fps found at the sensor camera output (an Andor Ixon+ DU-897ECSO EMCCD). Flexibility and parallel processing features of the reconfigurable logic have been used to implement a novel imaging strategy for segmented-mirror telescopes, allowing separate evaluation of every segment and posterior accumulation to achieve the resolution limit of a single segment with the integration capability of the full primary mirror.

Select this Article		The shutter and filter exchanger system of Hyper Suprime-Cam Shiang-Yu Wang, Eric J.-Y. Liaw, Yao-De Huang, Chyi-Fong Chiu, Dun-Zen Jeng, Yoshiyuki Doi, Fumihiro Uragachi, Yutaka Komiyama, and Satoshi Miyazaki Proc. SPIE 7014, 70144A (2008); http://dx.doi.org/10.1117/12.787483 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The next generation wide field camera HSC (Hyper Suprime-Cam) on Subaru telescope is planned to cover 1.5 degree diameter field with a focal plane size about 650mm. To minimize the impact to the telescope, the design for the elements of the camera is constraint to the tight space and weight limits. In order to fit the available space, the screen winding shutter and petal shape filter exchanger are designed for the HSC. The CFRP is used for the structure to minimize the load. In this report, the design and analysis for the shutter and filter exchanger system will be presented. The result for the shutter membrane tests will also be discussed.

Select this Article		EDiFiSE: equalized and diffraction-limited field spectrograph experiment B. García-Lorenzo, J. J. Fuensalida, M. A. C. Rodríguez-Hernández, A. Alonso, M. Barreto, F. Gracia-Temich, Y. Martín, L. F. Rodríguez, T. Viera, Y. Padilla, A. Fernández, and J. F. M. Escobar-Romero Proc. SPIE 7014, 70144B (2008); http://dx.doi.org/10.1117/12.787848 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present EDiFiSE, a prototype instrument for the observation of high-contrast systems, combining an adaptive optics (AO) system and an equalized integral field unit (EIFU). The design of the AO system takes into account the statistical behaviour of the atmospheric turbulence structure at the Canary Islands (Spain) astronomical observatories: Roque de los Muchachos (ORM) on the island of La Palma and Teide observatory (OT) in Tenerife. The AO will have the capability of adapting to the prevailing turbulence conditions; in this sense, the EDiFiSE AO unit will be an 'adaptable' adaptive optics system. The corrected beam feeds an hexagonal integral field unit formed by 331 micro-lenslets, which focus the intensity distribution at the focal plane into 331 optical fibers. The central seven fibers of the bundle include variable attenuators for the equalization of these fibers output intensities, matching them to the dynamical range of the detector and reducing the optical cross talk inside the spectrograph. This technique, called equalized integral field spectroscopy (Arribas, Mediavilla & Fuensalida 1998¹), permits to obtain spectral and spatial information of the equalized object and its surroundings as well as accurate relative photometry and astrometry.

Select this Article		Testing commercial variable fiber attenuators and lenslet arrays for equalized integral field spectroscopy applications F. Gracia-Temich, B. García-Lorenzo, Y. Padilla-Michel, J. F. M. Escobar-Romero, J. J. Fuensalida, M. A. C. Rodríguez-Hernández, J. L. Rasilla, C. Kuckein, and E. López-Rodríguez Proc. SPIE 7014, 70144C (2008); http://dx.doi.org/10.1117/12.787856 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have been testing at laboratory commercial variable attenuators commonly used in telecommunication applications for their used in astronomy. Such variable attenuators are going to be included in the central fibers of the integral field unit (IFU) of the prototype instrument EDiFiSE (Equalized and Diffraction-limited Field Spectrograph Experiment). The EDiFiSE IFU is conformed by a lenslet array of 331 lenses, 331 fibers and seven variable attenuators (inserted in the seven central fibers of the bundle). We present here the characterization of the attenuator devices tested for their use in astronomy and, in particular, to their application in the observation of object of large dynamic range using equalized integral field spectroscopy. We also present the optical tests we have carried out to characterize the performances of two lenslet arrays acquired in the framework of the EDiFiSE project.

Select this Article		Multi-object medium resolution optical spectroscopy at the E-ELT Paolo Spanò and Piercarlo Bonifacio Proc. SPIE 7014, 70144D (2008); http://dx.doi.org/10.1117/12.787948 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design of a compact medium resolution spectrograph (R~15,000-20,000), intended to operate on a 42m telescope in seeing-limited mode. Our design takes full advantage of some new technology optical components, like volume phase holographic (VPH) gratings. At variance with the choice of complex large echelle spectrographs, which have been the standard on 8m class telescopes, we selected an efficient VPH spectrograph with a limited beam diameter, in order to keep overall dimensions and costs low, using proven available technologies. To obtain such a resolution, we need to moderately slice the telescope image plane onto the spectrograph entrance slit (5-6 slices). Then, standard telescope AO-mode (GLAO, Ground Layer Adaptive Optics) can be used over a large field of view (~10 arcmin), without loosing efficiency. Multiplex capabilities can greatly increase the observing efficiency. A robotic pick-up mirror system can be implemented, within conventional environmental conditions (temperature, pressure, gravity, size), demanding only standard mechanical and optical tolerances. A modular approach allows us scaling multiplex capabilities on overall costs and available space.

Select this Article		A novel design of a fibre-fed high-resolution spectrograph for WFMOS Hanshin Lee, Gavin B. Dalton, and Ian A. J. Tosh Proc. SPIE 7014, 70144E (2008); http://dx.doi.org/10.1117/12.787982 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present a novel design of a fibre-fed high-resolution spectrograph (HRS hereafter) for WFMOS. WFMOS HRS is a multi-object spectrograph for studying the formation and evolution history of our Galaxy by measuring spectra of Galactic stars. In a 8m-class telescope, it aims to measure 1,500 stellar spectra simultaneously with spectral resolution between 25,000 and 40,000 in optical wavebands defined within 4000Å and 9000Å. For the HRS optical design, we have explored three disperser options: Volume Phase Holographic Grating (VPHGs), prism-immersed VPHG, and Echelle grating. Two camera designs have also been studied for the spectrograph camera optics, one tranmissive design and the other a Schmidt design. We also investigated a conjugate collimator design that allows two spectrographs to share a single grating so as to work as a single spectrograph.

Select this Article		SIDE: a fiber fed spectrograph for the 10.4 m Gran Telescopio Canarias (GTC) F. Prada, M. Azzaro, O. Rabaza, J. Sánchez, and M. Ubierna Proc. SPIE 7014, 70144F (2008); http://dx.doi.org/10.1117/12.787364 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract SIDE (Super Ifu Deployable Experiment) will be a second-generation,common-user instrument for the Grantecan (GTC) on La Palma (Canary Islands, Spain). It is being proposed as a spectrograph of low and intermediate resolution, highly efficient in multi-object spectroscopy and 3D spectroscopy. SIDE will feature the unique possibility of performing simultaneous visible and IR observations for selected ranges. The SIDE project is leaded by the Instituto de Astrofsica de Andaluca in Granada (Spain) and the SIDE Consortium is formed by a total of 10 institutions from Spain, Mexico and USA. The feasibility study has been completed and currently the project is under revision by the GTC project office.

Select this Article		PRL advanced radial-velocity all-sky search (PARAS): an efficient fiber-fed spectrograph for planet searches Abhijit Chakraborty, Eric Harvey Richardson, and Suvrath Mahadevan Proc. SPIE 7014, 70144G (2008); http://dx.doi.org/10.1117/12.788124 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present here the optical design of an efficient Fiber-fed, Prism Cross-dispersed, Echelle Spectrograph (Resolution ~70,000 @seeing limited ~2arcsecs conditions) which will operate in the wavelength region of 3700A to 8100A. It will be used for extra-solar planets searches down to the precision of 3m/s and as well as for follow-up observations for new transit discoveries. The spectrograph design is such that with a beam size of 100mm (4inch) it should suit the existing 1 to 2m class of telescopes available in India. The fiber-fed spectrograph will be installed with a 1.2m telescope, which is situated at Mt. Abu (5800feet), Rajasthan, India. We estimate the spectrograph to be >30% efficient from the slit to the CCD detector, and up to 15% efficient including sky, telescope, fiber-fed optics etc. We expect to reach the S/N ratio of 70 on a 10mag star for an integration time of 40mins. We aim to achieve 5m/s to 3m/s Radial Velocity accuracies on such a star using the simultaneous ThAr referencing method. Since thermal stability is absolutely necessary to achieve <5m/s RV accuracies, the whole spectrograph is planned to be kept inside a vibration free isolated tank under low vacuum (0.001 mbar) in a thermally isolated room at 28C +/- 0.01C. It should see the first light by the summer of 2009. We are guaranteed at least 120 nights per year for the planet search program, more nights are possible.

Select this Article		BESO: first light at the high-resolution spectrograph for the Hexapod-Telescope Ingo Steiner, Otmar Stahl, Walter Seifert, Rolf Chini, and Andreas Quirrenbach Proc. SPIE 7014, 70144H (2008); http://dx.doi.org/10.1117/12.788182 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract BESO (Bochum Echelle Spectrograph for OCA)is a high-resolution echelle spectrograph which has been built by Ruhr-Universitaet, Bochum and Landessternwarte Heidelberg. It is fiber-coupled to the 1.5m Hexapod-Telescope at the Observatario Cerro Armazones (OCA), Chile. The first light spectra show that the resolution of 48.000 over a spectral range from 370 nm to 840 nm has been achieved. An alignment by design approach has been followed to assemble the fiber-head optics at the telescope side of fiber coupled instrument.

Select this Article		Coupling LBT's double pupil into optical fibers F. Müller Sánchez, F. Eisenhauer, M. Haug, C. Gál, A. Krabbe, and T. M. Herbst Proc. SPIE 7014, 70144I (2008); http://dx.doi.org/10.1117/12.788445 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In the context of interferometric integral field spectroscopy at the LBT, we have investigated the physics of coupling light from a double pupil into optical fibers. Previous fiber-fed astronomical instruments solved the problem of coupling light from a single dish into single- and multi-mode fibers. However, this is an unexplored territory for a telescope configuration such as the LBT. We have investigated the coupling of the telescope's double pupil to optical fibers in detail, and present results from numerical simulations and preliminary measurements from an experimental setup.

Select this Article		Concepts for a high-resolution multi-object spectrograph for galactic archeology on the Anglo-Australian Telescope Samuel C. Barden, Jonathan Bland-Hawthorn, Vladimir Churilov, Simon Ellis, Tony Farrell, Ken C. Freeman, Roger Haynes, Anthony Horton, Damien J. Jones, Greg Knight, Stan Miziarski, William Rambold, Greg Smith, and Lew Waller Proc. SPIE 7014, 70144J (2008); http://dx.doi.org/10.1117/12.788549 \| Cited 3 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Mapping out stellar families to trace the evolutionary star formation history of the Milky Way requires a spectroscopic facility able to deliver high spectral resolution (R≥30k) with both good wavelength coverage (~400 Ang) and target multiplex advantage (~400 per 2 degree field). Such a facility can survey 1,200,000 bright stars over 10,000 square degrees in about 400 nights with a 4-meter aperture telescope. Presented are the results of a conceptual design study for such a spectrograph, which is under development as the next major instrument for the Anglo-Australian Observatory. The current design (that builds upon the AAOmega system) makes use of a White Pupil collimator and an R3 echelle that is matched to the existing AAOmega cameras. The fibre slit can be reconfigured to illuminate the Pupil relay side of the collimator mirror bypassing the echelle, thus preserving the lower dispersion modes of the AAOmega spectrograph. Other spectrograph options initially considered include use of an anamorphic collimator that reduces the required dispersion to that achievable with VPH grating technology or possible use of a double-pass VPH grating.

Select this Article		2dF grows up: Echidna for the AAT Andrew McGrath, Sam Barden, Stan Miziarski, William Rambold, and Greg Smith Proc. SPIE 7014, 70144K (2008); http://dx.doi.org/10.1117/12.788605 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the concept design of a new fibre positioner and spectrograph system for the Anglo-Australian Telescope, as a proposed enhancement to the Anglo-Australian Observatory's well-known 2dF facility. A four-fold multiplex enhancement is accomplished by replacing the 400-fibre 2dF fibre positioning robot with a 1600-fibre Echidna unit, feeding three clones of the AAOmega optical spectrograph. Such a facility has the capability of a redshift 1 survey of a large fraction of the southern sky, collecting five to ten thousand spectra per night for a million-galaxy survey.

Select this Article		Wide-field one-shot optical polarimeter: HOWPol Koji S. Kawabata, Osamu Nagae, Shingo Chiyonobu, Hiroyuki Tanaka, Hidehiko Nakaya, Mariko Suzuki, Yukiko Kamata, Satoshi Miyazaki, Kazuyoshi Hiragi, Hisashi Miyamoto, Masayuki Yamanaka, Akira Arai, Takuya Yamashita, Makoto Uemura, Takashi Ohsugi, et al. Proc. SPIE 7014, 70144L (2008); http://dx.doi.org/10.1117/12.788569 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract For prompt optical polarimetry of gamma-ray burst (GRB) afterglow, we require wide-field imaging polarimeter which can produce both Stokes Q and U parameters from only a single exposure, as well as quickly-moving telescope and enclosure system. HOWPol is an optical imaging polarimeter which provides four linearly polarized images at position angles of 0°, 45°, 90° and 135°, i.e., Stokes I, Q, U, simultaneously. The key device is the wedged double Wollaston prism described by Oliva (1997)¹ and Pernechele et al. (2003).² The images are focused on two 2k×4k fully depleted CCDs. We report the design and development of the optical devices of HOWPol, which will be mounted to the 1.5-m Kanata telescope at Hiroshima University and stand by the GRB alert.

Select this Article		Long slit spectroscopy for exoplanet characterization in SPHERE Arthur Vigan, Maud Langlois, Claire Moutou, and Kjetil Dohlen Proc. SPIE 7014, 70144M (2008); http://dx.doi.org/10.1117/12.788838 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Extrasolar planet observation and characterization is a major objective for astronomy in the coming decade. The Spectro-Polarimetric High contrast imager for Exoplanets Research (SPHERE) instrument for the Very Large Telescope (VLT) is currently under development to achieve this objective with greater performances than any existing instruments. It will have the capability to observe planets down to few masses of Jupiter at separations as small as 0.1 arcseconds from the central star thanks to dedicated extreme adaptive optics system and coronagraph. Planets characterization will be achieved with IRDIS, one of the 3 science modules of SPHERE, using its long slit spectroscopy (LSS) mode along with a Lyot coronagraph at low (~40) or medium (~400) resolution. Similarly to the dual-band imaging (DBI) technique dedicated to detection, the main limitation of the long slit spectroscopy is the speckles generated by instrumental static and quasi-static aberrations, especially when observing very close to the star. Another performance limitation is the chromatic dependence of the speckles in the field, known as speckle chromatism, which creates a modulation of the spectrum. Finally, we are also facing problems related to long slit spectroscopy, such as slit efficiency, thermal background and difficulty to preserve the spectrum continuum. Intensive simulations have been performed using the CAOS framework under IDL, in order to simulate realistic spectra in terms of signal, noise and instrumental artifacts. We present here in details the expected performances among with a detailed analysis of the various noise sources contributions. This analysis leads to a quantitative estimation of the characterization limitations and optimized data reduction procedures.

Select this Article		Proposed instrumentation for PILOT Will Saunders, Peter Gillingham, Andrew McGrath, Roger Haynes, John Storey, Jon Lawrence, Michael Burton, Charles Jenkins, and Alcione Mora Proc. SPIE 7014, 70144N (2008); http://dx.doi.org/10.1117/12.788858 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed Australian/European optical/infrared telescope for Dome C on the Antarctic Plateau, with target first light in 2012. The proposed telescope is 2.4m diameter, with overall focal ratio f/10, and a 1 degree field-of-view. In median seeing conditions, it delivers 0.3" FWHM wide-field image quality, from 0.7-2.5 microns. In the best quartile of conditions, it delivers diffraction-limited imaging down to 1 micron, or even less with lucky imaging. The areas where PILOT offers the greatest advantages are (a) very high resolution optical imaging, (b) high resolution wide-field optical imaging, and (c) all wide-field thermal infrared imaging. The proposed first generation instrumentation consists of (a) a fast, low-noise camera for diffraction-limited optical lucky imaging; (b) a gigapixel optical camera for seeing-limited imaging over a 1 degree field; (c) a 4K x 4K near-infrared (1-5 micron) camera with both wide-field and diffraction-limited modes; and (d) a double-beamed midinfrared (7-40 micron) camera.

Select this Article		Verification and acceptance tests of the PRIMA DDL optics Peter Bizenberger, Harald Baumeister, Uwe Graser, Thomas Henning, Nathalie Krause, Ralf Launhardt, Vianak Naranjo, Didier Queloz, and Andreas Quirrenbach Proc. SPIE 7014, 70144P (2008); http://dx.doi.org/10.1117/12.788994 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The last step in designing and building instruments are the verification and acceptance tests of the assembled units and of the final instrument. For instruments, which are engineered to work at the limit of feasibility, these tests must be accurate and stable at a level much better than the expected performance of the instrument. Particularly for interferometric instruments, this requires special care for the test planning and implementation in order to achieve the necessary performance. This paper describes the verification and acceptance tests of the PRIMA DDL optics in terms of wavefront error and tilt requirements as well as the assembling and aligning accuracy. We demonstrate the conformity of the optics and point out the limitations of the test methods.

Select this Article		The WIYN One Degree Imager: an update Daniel R. Harbeck, George H. Jacoby, Gary Muller, Dave Sawyer, Charles Harmer, Andrey Yeatts, John Cavin, and Charles Corson Proc. SPIE 7014, 70144Q (2008); http://dx.doi.org/10.1117/12.787444 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The WIYN Consortium is building the One Degree Imager (ODI) for its 3.5m telescope, located at Kitt Peak, Arizona (USA). ODI will utilize both the excellent image quality and the one degree field of view of the WIYN telescope. Image quality will be actively improved by localised tip/tilt image motion stabilisation using a novel concept of Orthogonal Transfer Array (OTA) CCDs, which are a new detector type jointly developed with the PanSTARRS project. Its anticipated median image quality of ≤ 0.55" in the R band will make ODI a unique and competitive instrument in the landscape of the next generation of large field imagers. A conceptual design of ODI was presented earlier at SPIE.¹ In the meantime, this concept matured, the ODI project has been fully funded, and it has entered the construction phase. A prototype camera (QUOTA) with a field of view of 16'x16' has already seen first star light in fall 2006. In this paper we report on the evolution of ODI's definition, the design of its components, the status of the OTA detector development, and the path towards first light in early 2010. In accompanying papers we detail the design of the ODI's optical corrector, the mechanical structures, and the software & instrument system control design.

Select this Article		Mechanical design of the WIYN One Degree Imager (ODI) Gary P. Muller, Daniel Harbeck, George H. Jacoby, Charles Harmer, Andrey Yeatts, Dan Blanco, John Cavin, and Dave Sawyer Proc. SPIE 7014, 70144R (2008); http://dx.doi.org/10.1117/12.789765 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The WIYN consortium is building the One Degree Imager (ODI) to be mounted to a Nasmyth port of the WIYN 3.5m telescope, located at Kitt Peak, Arizona (USA). ODI will utilize both the excellent image quality and the one-degree field of view that the telescope delivers. To accommodate the large field of view (~0.39m diameter unvignetted field with 0.54m across the diagonal of the one-degree-square, partially vignetted field), 0.6m-class optics are required. The ODI design consists of a two element corrector: one serves as a vacuum barrier to the cryostat, the other is an asphere; two independently rotating bonded prism pairs for atmospheric dispersion compensation (ADC); nine independently deployable filters via a simple pivoting motion; and a 971 mega-pixel focal plane consisting of 64 orthogonal transfer array (OTA) devices. This paper is an overview of the mechanical design of ODI and describes the optical element mounting and alignment strategy, the ADC & filter mechanisms, plus the focal plane. Additionally, the project status will be discussed. In accompanying papers Jacoby¹ describes ODI's optical design, Yeatts² describes the software and control system design, and Harbeck³ gives a general update on the project.

Select this Article		The WIYN One Degree Imager optical design George H. Jacoby, Charles Harmer, Daniel Harbeck, Gary Muller, Daniel Blanco, Joseph Keyes, and John Cavin Proc. SPIE 7014, 70144S (2008); http://dx.doi.org/10.1117/12.789998 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The main advantage of the WIYN One Degree Imager (ODI) over other wide-field imagers will be its exceptional image quality. The fine pixel scale (0.11") provides uncompromised sampling of stellar PSFs under most conditions (seeing >0.3"). The telescope routinely delivers the site seeing (median ~ 0.7") which is often below 0.5" FWHM, and can be as low as 0.25". The ODI specifications require the optics to maintain native high quality images. A two-element, fused silica, corrector meets the geometric error budget of 0.10" images, but the first element requires a mildly aspheric surface. The other element serves as the dewar window. A pair of cemented prisms (fused silica plus PBL6Y) serve as an ADC, which is essential to meet the image quality requirements for many observing programs. We describe the optical design details and its performance, the tolerances required, and the trade-offs considered for anti-reflection coatings. This paper is an update to a preliminary three-element design.

Select this Article		The Large Binocular Camera: description and performances of the first binocular imager R. Speziali, A. Di Paola, E. Giallongo, F. Pedichini, R. Ragazzoni, V. Testa, A. Baruffolo, C. De Santis, E. Diolaiti, J. Farinato, A. Fontana, S. Gallozzi, F. Gasparo, G. Gentile, A. Grazian, et al. Proc. SPIE 7014, 70144T (2008); http://dx.doi.org/10.1117/12.790132 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Since the very beginning of 2008, the Large Binocular Telescope (LBT) is officially equipped with it's first binocular instrument ready for science observations: the Large Binocular Camera (LBC). This is a double CCD imager, installed at the prime focus stations of the two 8.4m telescopes of LBT, able to obtain deep and wide field images in the whole optical spectrum from UV to NIR wavelengths. We present here the overall architecture of the instrument, a brief hardware review of the two imagers and notes how observations are carried on. At the end we report preliminary results on the performances of the instrument along with some images obtained during the first months of observations in binocular mode.

Select this Article		LBT report activities concerning the optomechanics alignment of the Large Binocular Camera's Red Channel G. Gentile, R. Ragazzoni, E. Diolaiti, J. Farinato, J. Hill, R. Bertam, and A. Baruffolo Proc. SPIE 7014, 70144U (2008); http://dx.doi.org/10.1117/12.790499 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In this article activities on the Optomechanics of the Prime Focus Red Channel alignment are described from the moment in which the instrument left Italy to be shipped to LBT site to the moment in which it has been successfully placed on the second LBT arm. An overview is given, starting from the realization of a "clean laboratory" at LBT, going through the alignment check and finally with the mounting operations of the instrument at the telescope and its alignment with the "second eye" primary mirror, with tolerances good enough to perform the fine alignment on the sky with the telescope Active Optics.

Select this Article		Hyper Suprime-Cam: camera dewar Yutaka Komiyama, Satoshi Miyazaki, Satoshi Kawanomoto, Tomoki Morokuma, Hidehiko Nakaya, Hisanori Furusawa, and Yoko Tanaka Proc. SPIE 7014, 70144V (2008); http://dx.doi.org/10.1117/12.788322 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We summarize the design of the camera dewar for Hyper Suprime-Cam (HSC) which is the next generation prime focus camera for the Subaru Telescope. The camera dewar consists of six main components; base flange, focal plane assembly, window assembly, wall assembly, front-end electronics asembly and back assembly. It is about 700 mm in diameter and 500 mm in height, accommodating 116 2k×4k full depletion type CCDs inside. The CCD packages, whose heights are accurately controlled (P-V ~ 25μm), are installed on a silicon-carbide cold plate of 10 μm flatness to ensure that the surface of CCDs is flat within the focal depth of the wide-field corrector (~ 34μm). The cold plate is supported rigidly and thermally isolated by support posts which are made of Zirconia. We carried out the deformation analysis and the thermal analysis of the dewar based on the finite-element analysis, and demonstrate that the design is feasible. We also show the assembly sequence of the dewar.

Select this Article		Hyper Suprime-Cam: autoguider and Shack-Hartmann systems Tomoki Morokuma, Yutaka Komiyama, Satoshi Miyazaki, Hidehiko Nakaya, Hisanori Furusawa, Daigo Tomono, Satoshi Kawanomoto, and Yoko Tanaka Proc. SPIE 7014, 70144W (2008); http://dx.doi.org/10.1117/12.788481 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present methodology of the autoguider (AG) and Shack-Hartmann (SH) sensing systems which will be used for a wide-field camera, Hyper Suprime-Cam (HSC), on the prime focus of the Subaru 8.2-m telescope. For both systems, stellar images are formed on the HSC science CCDs. Although light from AG stars must pass through bandpass filters, we can obtain enough photons for AG stars brighter than m_AB < 14 mag in any bandpass filter assumed in order to achieve accurate autoguiding. Spatial number density of such bright stars from the SDSS database requires an area of about two 2k×4k CCDs for AG stars. The optics of SH system except for the imaging CCDs is located within the HSC filter unit.

Select this Article		Hyper Suprime-Cam: CCD readout electronics Hidehiko Nakaya, Tomohisa Uchida, Hironao Miyatake, Hiroaki Aihara, Yoshiyuki Doi, Hisanori Furusawa, Hiroshi Karoji, Yukiko Kamata, Satoshi Kawanomoto, Yutaka Komiyama, Satoshi Miyazaki, Tomoki Morokuma, Manobu Tanaka, and Yoko Tanaka Proc. SPIE 7014, 70144X (2008); http://dx.doi.org/10.1117/12.789197 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Hyper Suprime-Cam is planned to employ about 120 2k×4k fully-depleted CCDs with 4 signal outputs for each. The data size of an image becomes larger than 2Gbytes. All of the CCDs are designed to be readout parallel within 20 seconds, and the readout noise is expected to be 5e. The frontend electronics will be mounted in a vacuumed cryostat, and connected to the backend electronics mounted on the outside of the cryostat. The frontend electronics includes entire analog circuits for CCD including CCD drivers, preamplifiers and ADC. The backend electronics consists of newly developed gigabit Ethernet modules combined with 2Gbytes memory modules, and several supporting boards. We will present the current status of the CCD readout electronics developments for HSC.

Select this Article		The 12K×8K CCD mosaic camera for the Palomar Transient Factory Gustavo Rahmer, Roger Smith, Viswa Velur, David Hale, Nicholas Law, Khanh Bui, Hal Petrie, and Richard Dekany Proc. SPIE 7014, 70144Y (2008); http://dx.doi.org/10.1117/12.788086 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Palomar Transient Factory is an automated wide-field survey facility dedicated to identifying a wide range of transient phenomena. Typically, a new 7.5 square degree field will be acquired every 90 seconds with 66% observing efficiency, in g' band when the sky is dark, or in R band when the moon is up. An imaging camera with a 12Kx8K mosaic of MIT/LL CCDs, acquired from CFHT, is being repackaged to fit in the prime focus mounting hub of the Palomar 48-inch Oschin Schmidt Telescope. We discuss how we have addressed the broad range of issues presented by this application: faster CCD readout to improve observing efficiency, a new cooling system to fit within the constrained space, a low impact shutter to maintain reliability at the fast observing cadence, a new filter exchange mechanism, and the field flattener needed to correct for focal plane curvature. The most critical issue was the tight focal plane alignment and co-planarity requirements created by the fast beam and coarse plate scale. We built an optical profilometer system to measure CCDs heights and tilts with 1 μm RMS accuracy.

Select this Article		HIPO data products E. W. Dunham, J. L. Elliot, T. A. Bida, P. L. Collins, B. W. Taylor, and S. Zoonematkermani Proc. SPIE 7014, 70144Z (2008); http://dx.doi.org/10.1117/12.788040 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract HIPO is a special purpose instrument for SOFIA, the Stratospheric Observatory For Infrared Astronomy. It is a high-speed, imaging photometer that will be used for a variety of time-resolved precise photometry observations, including stellar occultations by solar system objects and transits by extrasolar planets. HIPO will also be used during the test program for the SOFIA telescope, a process that began with a series of ground-based tests in 2004. The HIPO requirements, optical design, overall description, and an early look at performance and planned data acquisition modes have appeared in earlier papers (e.g. Dunham, et al., Proc. SPIE 5492, 592-603 (2004)). This paper provides an update to the instrument description, final lab measurements of instrument performance, and a discussion of the data produced by the various observing modes.

Select this Article		Compact multi-band visible camera for 1m-class fast telescopes Alberto Riva and Paolo Spanò Proc. SPIE 7014, 701450 (2008); http://dx.doi.org/10.1117/12.789200 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Most of the small 1m-class telescopes designed for fast tracking of transient object, like GRBs, are equipped with infrared and visible cameras, fed through a dichroic. We studied a new concept for a fast and compact multi-band visible camera, using successive dichroics, to cover simultaneously many visible bands (U,B,V,R, and I), sampled with one more CCD detectors. This extended spectral coverage will help to observe transient faint objects. To keep envelope size, weight and overall cost at a reasonable level, a trade-off has been carried out.

Select this Article		SNDICE: a direct illumination calibration experiment at CFHT C. Juramy, E. Barrelet, K. Schahmaneche, P. Bailly, W. Bertoli, C. Evrard, P. Ghislain, A. Guimard, J.-F. Huppert, D. Imbault, D. Laporte, H. Lebbolo, P. Repain, R. Sefri, A. Vallereau, et al. Proc. SPIE 7014, 701451 (2008); http://dx.doi.org/10.1117/12.789051 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the first results of the SuperNova Direct Illumination Calibration Experiment (SNDICE), installed in January 2008 at the Canada France Hawaii Telescope. SNDICE is designed for the absolute calibration of the instrumental response of a telescope in general, and for the control of systematic errors in the SuperNova Legacy Survey (SNLS) on Megacam in particular. Since photometric calibration will a critical ingredient for the cosmological results of future experiments involving instruments with large focal planes (like SNAP, LSST and DUNE), SNDICE functions also as a real-size demonstrator for such a system of instrumental calibration. SNDICE includes a calibrated source of 24 LEDs, chosen for their stability, spectral coverage, and their power, sufficient for a flux of at least 100 electron/s/pixel on the camera. It includes also Cooled Large Area Photodiode modules (CLAPs), which give a redundant measurement of the flux near the camera focal plane. Before installing SNDICE on CFHT, we completed a full calibration of both subsystems, including a spectral relative calibration and a 3D mapping of the beam emitted by each LED. At CFHT, SNDICE can be operated both to obtain a complete one-shot absolute calibration of telescope transmission in all wavelengths for all filters with several incident angles, and to monitor variations on different time scales.

Select this Article		An atmospheric corrector to work with FastCam at William Herchel Telescope Roberto López and Ariadna Calcines Proc. SPIE 7014, 701452 (2008); http://dx.doi.org/10.1117/12.789302 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In this contribution an Atmospheric Dispersion Corrector (ADC) developed for the FastCam project is presented. FastCam is a system based on 'lucky imaging' techniques for high spatial resolution, developed at the Instituto de Astrofisica de Canarias (IAC). The use of a system to correct the atmosphere's effects is necessary to obtain a good optics quality in order to satisfy science requirements. Two alternatives for an atmospheric dispersion corrector for the instrument FastCam have been studied. One ADC has been designed to be implemented and intended to correct that atmospherical effect at the 4.2m William Herschel Telescope (Roque de los Muchachos Observatory, La Palma) for zenithal distances larger than 15 degrees, mainly in I band. The excellent resolution reached with FastCam makes this effect to distort the images. This work presents the design of an ADC as a pre-focus system of two prisms with variable separation in order to compensate the dispersion until zenithal distances of 50°. Both are placed in a rotator to align the orientation of zenithal distorsion. The results for this ADC has been tested in lab, and in May 2008, at the WHT; our next step will be to use it at the 10.4m Gran Telescopio Canarias (GTC). Although the system is still under the final stages of its development, we want to implement it to the new instruments for high spatial resolution.

Select this Article		The Keck-I Cassegrain ADC Andrew C. Phillips, Joseph Miller, David Cowley, and Vernon Wallace Proc. SPIE 7014, 701453 (2008); http://dx.doi.org/10.1117/12.789930 \| Cited 3 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We briefly describe the design, construction and performance of the recently-commissioned Atmospheric Dispersion Corrector (ADC) for the Keck-I Cassegrain focus. This is a "longitudinal" ADC with fused silica prisms slightly over 1- meter in diameter, designed to operate at zenith distances up to 60 degrees and over a 20 arcminute field-of-view with negligible impact on image quality and throughput. It provides dispersion compensation from 0.31 to 1.1 microns. The sol-gel-based antireflection coatings were a major technological challenge, and we encountered some previously unrecognized performance consequences of the LADC design which should be considered before adopting this design.

Select this Article		The MagE spectrograph J. L. Marshall, Scott Burles, Ian B. Thompson, Stephen A. Shectman, Bruce C. Bigelow, Gregory Burley, Christoph Birk, Jorge Estrada, Patricio Jones, Matthew Smith, Vince Kowal, Jerson Castillo, Robert Storts, and Greg Ortiz Proc. SPIE 7014, 701454 (2008); http://dx.doi.org/10.1117/12.789972 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Magellan Echellette (MagE) spectrograph is a single-object optical echellette spectrograph for the Magellan Clay telescope. MagE has been designed to have high throughput in the blue; the peak throughput is 22% at 5600 Å including the telescope. The wavelength coverage includes the entire optical window (3100 Å - 1 μm). The spectral resolution for a 1" slit is R~4100. MagE is a very simple spectrograph with only four moving parts, prism cross-dispersion, and a vacuum Schmidt camera. The instrument saw first light in November 2007 and is now routinely taking science observations.

Select this Article		3D-NTT: a versatile integral field spectro-imager for the NTT M. Marcelin, P. Amram, P. Balard, C. Balkowski, O. Boissin, J. Boulesteix, C. Carignan, O. Daigle, M.-M. de Denus Baillargeon, B. Epinat, J.-L. Gach, O. Hernandez, F. Rigaud, and P. Vallée Proc. SPIE 7014, 701455 (2008); http://dx.doi.org/10.1117/12.800300 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The 3D-NTT is a visible integral field spectro-imager offering two modes. A low resolution mode (R ~ 300 to 6 000) with a large field of view Tunable Filter (17'x17') and a high resolution mode (R ~ 10 000 to 40 000) with a scanning Fabry-Perot (7'x7'). It will be operated as a visitor instrument on the NTT from 2009. Two large programmes will be led: "Characterizing the interstellar medium of nearby galaxies with 2D maps of extinction and abundances" (PI M. Marcelin) and "Gas accretion and radiative feedback in the early universe" (PI J. Bland Hawthorn). Both will be mainly based on the Tunable Filter mode. This instrument is being built as a collaborative effort between LAM (Marseille), GEPI (Paris) and LAE (Montreal). The website adress of the instrument is : http://www.astro.umontreal.ca/3DNTT

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Posters: Instrumentation Techniques and Technologies

Select this Article		Commissioning of an integral-field spectro-polarimeter for PMAS Ulrike Lemke, Andreas Kelz, Svend M. Bauer, Thomas Hahn, Emil Popow, and Martin M. Roth Proc. SPIE 7014, 701456 (2008); http://dx.doi.org/10.1117/12.789370 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract During 2007, a new polarimetric observing mode was added to the existing integral-field spectrograph PMAS. Initially, this instrumental upgrade is aimed to measure the linear polarization states and to determine the three Stokes parameters I, Q and U. The PMAS instrument offers an integral-field of view of up to 256 square arcseconds, while the spectrograph covers a wavelength region from 340 to 900 nm. The paper presents the opto-mechanical design of the polarimetric unit, summarizes calibration and test results and describes the first data taken during commissioning at the Calar Alto observatory. Given the range of applications and the large parameter space (two spatial coordinates, one wavelength dimension, plus polarimetric information), the realization of the PMAS 2D-Spectro-Polarimeter provides a unique capability for night-time astrophysical observations, such as the study of scattering processes or magnetic fields for a range of astronomical targets.

Select this Article		Comparison of precipitable water vapour measurements made with an optical echelle spectrograph and an infrared radiometer at Las Campanas Observatory Richard R. Querel, David A. Naylor, Joanna Thomas-Osip, Gabriel Prieto, and Andrew McWilliam Proc. SPIE 7014, 701457 (2008); http://dx.doi.org/10.1117/12.789365 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present simultaneous precipitable water vapour (PWV) measurements made at the Las Campanas Observatory in late 2007 using an Infrared Radiometer for Millimetre Astronomy (IRMA) and the Magellan Inamori Kyocera Echelle (MIKE) optical spectrograph. Opacity due to water vapour is the primary concern for ground based infrared astronomy. IRMA has been developed to measure the emission of rotational transitions of water vapour across a narrow spectral region centred around 20 μm, using a 0.1 m off-axis parabolic mirror and a sophisticated atmospheric model to retrieve PWV. In contrast, the MIKE instrument is used in conjunction with the 6.5 m Magellan Clay telescope, and determines the PWV through absorption measurements of water vapour lines in the spectra of telluric standard stars. With its high spectral resolution, MIKE is able to measure absorption from optically thin water vapour lines and can derive PWV values using a simple, single layer atmospheric model. In an attempt to improve the MIKE derived PWV measurements, we explore the potential of fitting a series of MIKE water vapour line measurements, having different opacities.

Select this Article		Calibration issues for MUSE Andreas Kelz, Martin Roth, Svend Bauer, Joris Gerssen, Thomas Hahn, Peter Weilbacher, Uwe Laux, Magali Loupias, Johan Kosmalski, Richard McDermid, and Roland Bacon Proc. SPIE 7014, 701458 (2008); http://dx.doi.org/10.1117/12.789407 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Multi-Unit Spectroscopic Explorer (MUSE) is an integral-field spectrograph for the VLT for the next decade. Using an innovative field-splitting and slicing design, combined with an assembly of 24 spectrographs, MUSE will provide some 90,000 spectra in one exposure, which cover a simultaneous spectral range from 465 to 930nm. The design and manufacture of the Calibration Unit, the alignment tests of the Spectrograph and Detector sub-systems, and the development of the Data Reduction Software for MUSE are work-packages under the responsibility of the AIP, who is a partner in a European-wide consortium of 6 institutes and ESO, that is led by the Centre de Recherche Astronomique de Lyon. MUSE will be operated and therefore has to be calibrated in a variety of modes, which include seeing-limited and AO-assisted operations, providing a wide and narrow-field-of-view. MUSE aims to obtain unprecedented ultra-deep 3D-spectroscopic exposures, involving integration times of the order of 80 hours at the VLT. To achieve the corresponding science goals, instrumental stability, accurate calibration and adequate data reduction tools are needed. The paper describes the status at PDR of the AIP related work-packages, in particular with respect to the spatial, spectral, image quality, and geometrical calibration and related data reduction aspects.

Select this Article		MUSE: feeding and mounting 24 spectrographs Harald Nicklas, Walter Seifert, Wenli Xu, Denni Hofmann, Christof Köhler, and Magali Loupias Proc. SPIE 7014, 701459 (2008); http://dx.doi.org/10.1117/12.789188 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Multi Unit Spectroscopic Explorer MUSE is an integral field device containing 24 spectrographs at the Nasmyth focus of the VLT unit telescope. The total field size of 1'x1' needs to be split and separated into 24 sub-fields which are relayed along a central structure into the entrance aperture of the individual spectrographs. The realization of the optics for field splitting and separation as well as the relay optics to direct the light of the individual fields to the spectrographs is described here. A very tight link exists between the relay optics system layout and the mechanical arrangement of the spectrographs in the common central structure. A compact mounting is essential due to the restricted space for such a large instrument even on the VLT Nasmyth platform. A suitable arrangement of vertical and horizontal stacking of the spectrographs was found enabling their feeding from the unobstructed front side of the instrumental structure. The central instrument mount was designed as a stiff structure absorbing print-through effects due to thermal mismatch with the telescope platform but rigid enough to withstand earthquakes.

Select this Article		The GlobalJetWatch spectrographs: a fibre-fed spectrograph for small telescopes Fraser J. Clarke, Andrew J. Gosling, Sam Doolin, Paul Goodall, Sebastian Perez, Paul Pattinson, Rick Makin, and Katherine M. Blundell Proc. SPIE 7014, 70145A (2008); http://dx.doi.org/10.1117/12.789236 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The GlobalJetWatch project (www.globaljetwatch.net) will place small (0.5-metre) commerical telescopes in four schools around the world. Each telescope will be equipped with a custom designed spectrograph, currently being built by the Astrophysics sub-department of the University of Oxford. The scientific goal of the project is to provide continual monitoring of a rosetta stone object, the micro-quasar SS433. In addition, the project has a significant out-reach element, aiming to involve school children on four-continents in front-line astronomical research. The spectrograph is a fibre-fed fixed format cross-dispersed echellete design providing R~6000 spectra from 4300-8500 in a single exposure. The spectrograph is built almost entirely from off-the-shelf components. The four GlobalJetWatch sites (Australia, India, South Africa, Chile) will be commissioned in 2008/09. Here we present the baseline design of the spectrograph, and initial results from the prototype on-sky commissioning in Oxford.

Select this Article		Optical design of the VLT Coude path for visible-range instrumentation G. Avila Proc. SPIE 7014, 70145B (2008); http://dx.doi.org/10.1117/12.789442 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes a proposed optical design for the ESO-VLT Coude path in the visible spectral range (380 to 800 nm). The optical train will be implemented in the four VLT Telescope Units in Paranal Observatory with the aim to feed simultaneously a high resolution - high stable spectrograph in the Combined Coude Laboratory. Cost - performances trade-offs are discussed as well.

Select this Article		The PAU camera Francisco J. Castander Proc. SPIE 7014, 70145C (2008); http://dx.doi.org/10.1117/12.789497 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Physics of the Accelerating Universe (PAU) is a new project whose main goal is to measure the baryon acoustic oscillations (BAO) in the galaxy distribution to characterize dark energy. For this purpose, it will build a new large field of view camera (the PAU Camera) to carry out a wide area imaging survey with narrow band filters spanning the optical wavelength range. The PAU Camera is at an early stage of design. Currently, it is designed to have a focal plane field of view of approximately 45cm in diameter, that will be densely populated by state of the art CCDs. The PAU Camera will use a new set of approximately 45 narrow band filters ranging from ~4200 to ~8700 angstroms with two additional wide band filters at the blue and red ends of the spectrum. The camera will operate in drift-scan mode. The PAU Camera is expected to be mounted either in a purposely designed 2.5m class wide field telescope or in an existing telescope that could be adapted to deliver a wide field.

Select this Article		HERMES: a high-resolution fiber-fed spectrograph for the Mercator Telescope Gert Raskin and Hans Van Winckel Proc. SPIE 7014, 70145D (2008); http://dx.doi.org/10.1117/12.789679 \| Cited 2 times Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract HERMES, a fiber-fed , high-resolution echelle spectrograph is currently in its integration phase at the 1.2-meter Mercator Telescope at the Roque de Los Muchachos Observatory on La Palma (Spain). The design of HERMES, optimized for high efficiency and high instrumental stability, is based on a large R2.7 echelle grating. It is operating in quasi-Littrow white-pupil configuration, with a double-prism as cross-disperser. It records the complete spectrum from 377 to 900 nm on one 2048×4608 pixel CCD in a single exposure. HERMES offers 1) a high-resolution and high-efficiency observation mode through a 80-μm optical fiber (2.5 arcsec sky aperture) equipped with a two-slice image slicer, resulting in a spectral resolution of R=85000 and a peak-efficiency above 25%; and 2) a high-stability mode through a 60-μm fiber (2.15 arcsec sky aperture, R=55000) equipped with a double fiber scrambler for improved spectrograph illumination stability. This mode is intended for high-precision radial velocity measurements and it offers the possibility of recording simultaneously the spectrum of a wavelength calibration lamp interlaced with the science spectrum. This allows for precise tracking of instrumental drifts during integration. To increase instrumental stability further, the spectrograph will be housed in a temperature and pressure controlled chamber. This spectrograph mounted on a flexible-scheduling telescope has a wide astronomical scope, going from asteroseismology to binary star research and chemical studies of stars and circumstellar material. In this contribution we present the final design of HERMES and we report on the project status.

Select this Article		A new two channel high-speed photo-polarimeter (HIPPO) for the SAAO Stephen Potter, David Buckley, Darragh O'Donoghue, James O'Conner, Piet Fourie, Geoff Evans, Craig Sass, Lisa Crause, O. W. Butters, Andrew Norton, Koji Mukai, and Martin Still Proc. SPIE 7014, 70145E (2008); http://dx.doi.org/10.1117/12.789716 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We report on the completion of a new 2 channel, HIgh speed Photo-POlarimeter (HIPPO) for the 1.9m optical telescope of the South African Astronomical Observatory. The instrument makes use of rapidly counter-rotating (10Hz), super-achromatic half- and quarter-waveplates, a fixed Glan-Thompson beamsplitter and two photo-multiplier tubes that record the modulated O and E beams. Each modulated beam permits an independent measurement of the polarisation and therefore simultaneous 2 filter observations. All Stokes parameters are recorded every 0.1sec and photometry every 1 millisecond. Post-binning of data is possible in order to improve the signal. This is ideal for measuring e.g. the rapid variability of the optical polarisation from magnetic Cataclysmic Variable stars. First light was obtained in February 2008.

Select this Article		MMT-Pol: an adaptive optics optimized 1-5μm polarimeter C. Packham and T. J. Jones Proc. SPIE 7014, 70145F (2008); http://dx.doi.org/10.1117/12.789796 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract MMT-POL is an adaptive optics optimized, 1-5μm imaging polarimeter for use at the 6.5m MMT. By taking full advantage of the adaptive optics secondary mirror of the MMT, this polarimeter will offer for the first time on 8m class telescopes, diffraction limited polarimetry with very low instrumental polarization. This instrument will permit observations as diverse as protoplanetary discs, comets, red giant winds, galaxies and AGN. We discuss both the novel instrument design and key science drivers.

Select this Article		Structure of the spectrograph ESOPO G. Sierra, A. Farah, J. Gonzalez, M. Pedrayes, M. Arroyo, G. Avila, F. Cobos, E. Colorado, A. Córdova, R. Costero, O. Chapa, J. Echevarria, B. García, F. Garfias, G. Guisa, et al. Proc. SPIE 7014, 70145G (2008); http://dx.doi.org/10.1117/12.789683 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The structure of the spectrograph ESOPO is the stiff mount that will maintain fixed all optics elements, electronics and mechanical subsystems. The ESOPO spectrograph is a project of the "Instituto de Astronomia de la Universidad Nacional Autonoma de Mexico" (IAUNAM) to upgrade its 2.1m telescope as a competitive facility for the next decade. The scientific purpose is to obtain a modern high efficient intermediate-low dispersion spectrograph optimized for the 3500 - 9000 Å spectral interval with a spectral resolution of 500 ≤ R ≤ 5000. It is to be used at the cassegrain f/7.5 focus of the 2.1 m telescope for general astronomical purposes. This work presents the mechanical design process and the form in which the structure was verified to comply with the ESOPO's top level image quality and stability requirements. The latter was not a lineal process. The way we resolved it is to run FEAs on the complete system and with the instrument in different operation positions during a normal cycle of observations. These results are validated through the error budget of the ESOPO. The structure is currently under construction.

Select this Article		Slit-mask, acquisition, and guiding zone mechanisms of the ESOPO spectrograph M. Pedrayes, J. Gonzalez, E. Luna, F. Quiroz, G. Sierra, M. Arroyo, G. Avila, F. Cobos, E. Colorado, A. Córdova, R. Costero, O. Chapa, J. Echevarria, A. Farah, B. García, et al. Proc. SPIE 7014, 70145H (2008); http://dx.doi.org/10.1117/12.789867 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This work presents the specifications, requirements, design, finite element analysis and results of the assembled subsystems: slit-mask, and the acquisition and guiding zone mechanisms of the ESOPO spectrograph. This spectrograph is a project of the Institute of Astronomy, National University of Mexico.

Select this Article		Two campaigns to compare three turbulence profiling techniques at Las Campanas Observatory Joanna Thomas-Osip, Edison Bustos, Michael Goodwin, Charles Jenkins, Andrew Lambert, Gabriel Prieto, and Andrei Tokovinin Proc. SPIE 7014, 70145I (2008); http://dx.doi.org/10.1117/12.789957 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In preparation to characterize the Giant Magellan Telescope site and guide the development of its adaptive optics system, two campaigns to systematically compare the turbulence profiles obtained independently with three different instruments were conducted at Las Campanas Observatory in September, 2007 and January 2008. Slope detection and ranging (SLODAR) was used on the 2.5-m duPont telescope. SLODAR measures the C²_n profile as a function of altitude through observations of double stars. The separation of the observed double star sets the maximum altitude and height resolution. Ground layer (altitudes < 1 km) and free atmosphere turbulence profiles are compared with those obtained with a lunar scintillometer (LuSci) and a multi-aperture scintillation sensor (MASS), respectively. In addition, the total atmospheric seeing was measured by both SLODAR and a differential image motion monitor (DIMM).

Select this Article		On-board calibration monitor for tracking instrument sensitivity J. W. Kruk, M. E. Kaiser, S. R. McCandliss, J. Orndorff, R. H. Barkhouser, D. J. Sahnow, D. J. Benford, R. C. Bohlin, S. E. Deustua, W. V. Dixon, P. D. Feldman, J. P. Gardner, R. A. Kimble, R. Kurucz, M. Lampton, et al. Proc. SPIE 7014, 70145J (2008); http://dx.doi.org/10.1117/12.790200 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The On-board Calibration Monitor (OCM) is being developed as an integral component of the ACCESS instrument and as a pathfinder for other missions. It provides stable full-aperture illumination of the telescope for tracking the instrument sensitivity as a function of time. The light source is composed of an ensemble of LED pairs with central wavelengths that span the spectral range of the instrument and illuminate a diffuser that is observed by the full optical path. Feedback stabilization of the light source intensity is achieved by photodiode monitoring of each LED. This stable source will provide real time knowledge of the ACCESS sensitivity throughout the 5-year duration of the program. The present status of the design and laboratory evaluation of the OCM system will be presented.

Select this Article		FMOS: the Fibre Multi-Object Spectrograph: Part VII. Results of PIR engineering run Masahiko Kimura, Toshinori Maihara, Fumihide Iwamuro, Masayuki Akiyama, Naoyuki Tamura, Naruhisa Takato, Kouji Ohta, and Shigeru Eto Proc. SPIE 7014, 70145K (2008); http://dx.doi.org/10.1117/12.790252 Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Fibre Multi-Object Spectrograph (FMOS) is the next common-use instrument of Subaru Telescope. FMOS consists of three subsystems; the Prime focus unit for Infrared (PIR), the fibre positioning system/connector units, and the two infrared spectrographs. The PIR was transferred to the Subaru Observatory in the spring of 2005 to check the optical performance on the telescope. As a result of the test observation, we found that the adjustment of the optical axis between PIR and the primary mirror was difficult with the initial design of the corrector alignment stage. Furthermore, the optical axis of the telescope moved over a little owing to an earthquake in Hawaii Island in Oct. 2006. Therefore we decided to modify mechanical structure of PIR, the corrector alignment stage as well as the cable wrapping system. This modification was completed in the summer of 2007. In this proceeding, we report the mechanical structure of the new PIR and the results of the engineering observations.

Select this Article		Design and construction of the fibre system for FMOS Graham J. Murray, George N. Dodsworth, Robert Content, and Naoyuki Tamura Proc. SPIE 7014, 70145L (2008); http://dx.doi.org/10.1117/12.790411 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract A consortium of Japanese, Australian and UK groups has developed a fibre-fed near IR (J & H band) multi-object spectrographic facility (FMOS) for the Subaru telescope. In this second-generation instrument, a novel prime focus 400-fibre multi-object positioning system, ECHIDNA, is optically linked via twin cables to dual IR spectrographs. The spectrographs are located some distance away, on a dedicated platform two levels above Nasmyth. The Centre for Advanced Instrumentation at Durham University oversaw the design and construction of the optical fibre system linking ECHIDNA to the spectrographs. A modularised connector within the cable scheme and an integral back illumination unit additionally featured as part of the Durham work-package. At the time of writing (mid 2008) FMOS, including the fibre system, is installed and functional on-telescope, with commissioning currently underway. This paper provides an overview of the design and construction of the optical fibre system.

Select this Article		NEFER: a high resolution scanning Fabry-Perot spectrograph Margarita Rosado, Abel Bernal, Jordi Cepa, Luis A. Martínez, and Arturo Iriarte Proc. SPIE 7014, 70145M (2008); http://dx.doi.org/10.1117/12.790145 \| Cited 1 time Online Publication Date: Jul 11, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The scanning Fabry-Perot spectrograph could give highly accurate, kinematical information of star forming regions (HH objects, protoplanetary disks and large scale flows) and the dynamics of isolated and interacting galaxies (resonances, galaxy pairs, compact groups). In this project we are developing a high spectral resolution scanning Fabry-Perot interferometer for the GTC 10 m telescope and the OSIRIS instrument. The system will provide the following characteristics: high spectral resolution data (R up to 20000) over a whole field of view of approximate 8 × 8 arcmin, 0.125 arcsec pixel size in two spectral ranges; 6300 to 7000 Å (galactic projects) and 8000 to 9500 Å (OTELO objects kinematics). ICOS ET100 Fabry-Perot will be used and installed within the OSIRIS collimated beam in the filter wheel hosting the tunable filters. Several acquisition software features have been defined like: synchronizing Fabry-Perot scanning with image acquisition, data cube assembly; single frame or data cube files would be provided according to the observer data reduction process. Fabry-Perot plates parallelism is extremely important to improve Finesse. Our team has developed an algorithm to accomplish this task.

Select this Article		GHαFaS: galaxy Hα Fabry-Perot system for the WHT Claude Carignan, Olivier Hernandez, Jean-Luc Gach, Philippe Balard, Marie-Maude De Denus-Baillargeon, Kambiz Fathi, John Beckman, and Jean Koulidiati Proc. SPIE 7014, 70145N (2008); http://dx.doi.org/10.1117/12.790616 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract GHαFaS is a new Fabry-Perot system available at the William Herschel Telescope. It was mounted, for the first time, at the Nasmyth focus of the 4.2 m WHT in La Palma in 2007 July. With a spectral resolution of the order R~15000 and a seeing limited spatial resolution, GHαFaS provides a new look at the Hα-emitting gas over a 4 arcminutes circular field in the nearby universe. Many types of objects can be observed with a scanning Fabry-Perot system on a 4.2 m class telescope such as galaxies, HII regions, planetary nebulae, supernova remnants outflows from stars and the diffuse interstellar medium. Astronomers from the Laboratoire d'Astrophysique Experimentale (LAE) in Montreal, the Laboratoire d'Astrophysique de Marseille (LAM), and the Instituto de Astrofisica de Canarias (IAC), have inaugurated GHαFaS by studying in detail the dynamics of nearby spiral galaxies. A robust set of tools for reducing and analyzing the data cubes obtained with GHαFaS has also been developed.

Select this Article		Stabilized-speckle integral field spectroscopy: SPIFS Stephen S. Eikenberry, Mark Keremedjiev, and Joseph C. Carson Proc. SPIE 7014, 70145P (2008); http://dx.doi.org/10.1117/12.788333 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe an instrument concept and basic feasibility study for a new observational technique which we call Stabilized-sPeckle Integral Field Spectroscopy (SPIFS). SPIFS will enable, under certain observational conditions and constraints, low-to-modest-Strehl diffraction-limited imaging spectroscopy from large ground-based telescopes in the optical bandpass (i.e. V, R, and I bands). SPIFS is capable of exploring important scientific niches which are not currently available using existing high angular resolution techniques such as adaptive optics or speckle imaging, using existing, relatively-inexpensive technology. Based on our simulations presented in a companion paper (Keremedjiev, Eikenberry & Carson, 2008), SPIFS can provide integral field spectroscopy at ~15-mas resolution and ~3% Strehl over the I-band with sky coverage of ~20% to 100% in the Galactic Plane and ~5% at the Galactic poles. We present an overview of the SPIFS technique and simulated performance in realistic observations of the microquasar SS 433 to demonstrate one simple example of the power of SPIFS.

Select this Article		SPIFS performance simulations: achieving diffraction-limited spatial resolutions for spectroscopy M. Keremedjiev, S. S. Eikenberry, and J. C. Carson Proc. SPIE 7014, 70145Q (2008); http://dx.doi.org/10.1117/12.788403 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the results of performance simulations characterizing the Stabilized sPeckle Integral Field Spectrograph (SPIFS). Our simulations of images distorted by Kolmogorov atmospheric turbulence confirm that stabilization of the single brightest speckle via a fast steering mirror (FSM) produces near-diffraction-limited spatial resolution for the red part of the visible spectrum (0.6 μm-1.0 μm). On a 10-meter class telescope this corresponds to an angle of ~13 mas. We also demonstrate that the Strehl ratio of the stabilized speckle will be between 1 and 3% for r₀ = 20cm on a 10-meter class telescopes. The guide star limiting magnitude, through the use of a shutter, will be I=16.5. Simulations also reveal that the guide star can be as far away as 20" from the source and still recover tip-tilt information to drive SPIFS.

Select this Article		Visitor instruments in the ESO Very Large Telescope Observatory in Paranal Pascal Robert Proc. SPIE 7014, 70145R (2008); http://dx.doi.org/10.1117/12.786607 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This paper is presenting the implementation of the concept of a Visitor Instrument at the Very Large Telescope observatory of ESO at Paranal. The focus on the Nasmyth A of Melipal UT#3 (8m telescope) is dedicated to receive these Visitor Instruments. This concept consists in the installation of an Instrument at the Visitor focus for an observation run for a limited period of time, and then to remove the instrument. The selection of the instrument is done according to its scientific and innovative outcome compared to the other ESO instruments already existing in the observatory. Once granted an observation run of several nights, the visitor Instrument has to show its compliance with the requirements of Paranal Observatory. Then the implementation and integration of the Visitor Instrument are scheduled according to the needs of the Institute who developed the instrument. The instrument is installed at Paranal with the support of ESO staff. The Visitor Instrument can be operated in 2 different modes according to its level of compliance to the ESO specifications. Immediately after the observation run is finished, the instrument is removed from the Visitor Focus.

Select this Article		New read-out electronics concept for visual and infrared detector arrays in astronomical instrumentation Karl Wagner, Ulrich Mall, José Ramos, and Ralf Klein Proc. SPIE 7014, 70145S (2008); http://dx.doi.org/10.1117/12.787386 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract With the building of scientific camera systems for astronomical purposes in mind, the Max-Planck-Institut fuer Astronomie (MPIA) has recently started developing new visual and infrared detector Read-out systems. Due to the modular design, the electronics components can be configured for a wide range of currently available IR-detectors and CCDs. The new Read-out Electronics are able to handle single or multiple detector systems with up to 144 input channels, feature high-speed data transfer and low power dissipation and additionally the system size is small and lightweight. The design is divided in four functional groups: controller board with variable Pattern Generator and fast fiber link, clock/bias board, analog to digital converter board and the PCI data receiver board which writes the incoming data into the computer memory. This design is highly versatile and allows for a wide variety of applications. The high data transfer rate, small size and low heat dissipation makes these Read-out Electronics ideal for relatively large focal plane arrays. The first instrument running with the new Read-out Electronics will be PANIC (Panoramic Near Infrared Camera) at the 2.20 m telescope on Calar Alto.

Select this Article		Results of X-shooter data reduction software on laboratory frames P. Goldoni, F. Royer, M. Horrobin, P. François, L. Guglielmi, R. Haigron, J. Vernet, A. Modigliani, and P. Bristow Proc. SPIE 7014, 70145T (2008); http://dx.doi.org/10.1117/12.787844 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the current state of the Data Reduction Software (DRS) being developed at APC, Paris Observatory, Amsterdam University and ESO for the X-shooter echelle spectrograph. X-shooter is the first VLT second generation instrument, which will have its first light during the fall of the current year and will be available to the astronomical community starting April 2009. The DRS will be fully integrated in the ESO VLT data flow environment and it will use the ESO Common Pipeline Library. X-shooter data have two main characteristics, on the one hand the exceptionally wide band (0.3 - 2.4 micron) covered in a single exposure, and on the other hand the spectral format with highly curved orders and tilted lines. After a brief description of the reduction process, the main results obtained up to now on simulated and laboratory data are reported. In particular the precision of wavelength calibration and sky subtraction are discussed.

Select this Article		Wavelength calibration sources for instruments on extremely large telescopes Maria Aldenius, Florian Kerber, Paul Bristow, Gillian Nave, Yuri Ralchenko, and Craig J. Sansonetti Proc. SPIE 7014, 70145U (2008); http://dx.doi.org/10.1117/12.787886 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Extremely large telescopes (ELTs) and most of their instruments will be optimized for operating in the near infrared (IR) because of the wavelength dependent performance of adaptive optics. Few established sources for wavelength calibration exist in this wavelength domain. This project aims to provide the basic data to select the best calibration sources for instruments at the European ELT (E-ELT) as a function of wavelength range and spectral resolution. We have made use of the existing databases such as the NIST Atomic Spectra Database as well as first principle physics and practical considerations to select about 20 hollow cathode lamps for study. We are investigating their spectral and operational properties through laboratory measurements using a Fourier Transform spectrometer at the European Southern Observatory (ESO). The most interesting sources will then be studied at atomic physics laboratories, such as the US National Institute of Standards and Technology (NIST), in order to produce accurate wavelength standards and calibration reference data directly applicable to operations of E-ELT instruments. The resulting data archive will be used to recommend the best suited sources for the instruments proposed for the E-ELT.

Select this Article		Selection of wavelength calibration features for automatic format recovery in astronomical spectrographs Paul Bristow and Florian Kerber Proc. SPIE 7014, 70145V (2008); http://dx.doi.org/10.1117/12.789034 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Automated wavelength calibration requires line lists that are free of blended or unstable features at the resolution of the spectrograph in order to avoid false matches. We present a procedure that will identify isolated features suitable for use as wavelength standards. The procedure takes into account the expected signal to noise level and the degree of uncertainty in the spectral format that defines how isolated the spectral features must be. Our goal is to produce a customised list of features that can be unambiguously matched to observed features.

Select this Article		Investigation of residual blaze functions in slit-based echelle spectrograph Petr Škoda, Brankica Šurlan, and Sanja Tomić Proc. SPIE 7014, 70145X (2008); http://dx.doi.org/10.1117/12.789284 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have studied the Residual Blaze Functions (RBF) resulting from division of individual echelle orders by extracted flat-field in spectra obtained by slit-fed OES spectrograph of 2m telescope of Ondrejov observatory, Czech Republic. We have eliminated the dependence on target and observation conditions by semiautomatic fitting of global response function, thus getting the instrument-only dependent part, which may be easily incorporated into data reduction pipeline. The improvement of reliability of estimation of continuum on spectra of targets with wide and shallow lines is noticeable and the merging of all orders into the one long spectrum gives much more reliable results.

Select this Article		ACCESS: absolute color calibration experiment for standard stars Mary Elizabeth Kaiser, Jeffrey W. Kruk, Stephan R. McCandliss, David J. Sahnow, Bernard J. Rauscher, Dominic J. Benford, Ralph C. Bohlin, S. E. Deustua, W. V. Dixon, P. D. Feldman, J. P. Gardner, R. A. Kimble, R. Kurucz, M. Lampton, H. W. Moos, et al. Proc. SPIE 7014, 70145Y (2008); http://dx.doi.org/10.1117/12.790106 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract ACCESS is a recently approved rocket-borne payload with a ground-based calibration and performance monitoring program that is designed to transfer the National Institute of Standards and Technology (NIST) absolute laboratory standards to the stars with a precision and calibration accuracy of 1% across the 0.35-1.7μm bandpass. This represents a significant improvement in the absolute and relative astrophysical flux calibration system, particularly at near-infrared (NIR) wavelengths. Establishing improved spectrophotometric standards is important for a broad range of missions and is relevant to many astrophysical problems. In particular, the precise calibration of the flux scale across the bandpass extending from 0.35-1.7 μm is fundamental to the precise determination of dark energy measurements based on SNeIa photometry.

Select this Article		A high-resolution spectrograph for the solar telescope GREGOR Manuel Collados, A. Calcines, J. J. Díaz, E. Hernnádez, R. López, and E. Páez Proc. SPIE 7014, 70145Z (2008); http://dx.doi.org/10.1117/12.790060 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This communication shows the design, layout, mounting and start-up of a high-resolution grating spectrograph for VIS-NIR at GREGOR 1.5m Solar Telescope (Observatorio del Teide, Tenerife, Canary Islands). The instrument will be used together with the Tenerife Infrared Polarimeter (TIP-II). As special characteristics of the design, the following can be mentioned: The first folding mirror of the spectrograph can be placed in two positions to take into account the change of the optical axis introduced by the polarizing beamsplitter of TIP-II. This way the instrument is optimally aligned when used in situations with and without polarimeter. The second and third mirrors rotate the image of the entrance slit, making it parallel to the grating grooves. A system of prisms are used to adequately fit onto the detector the two orthogonal polarized beams generated by the polarimeter. Two output beams are possible, to make feasible simultaneous visible and near-infrared observations.

Select this Article		An intelligent modulator system George Luis, Jack Harvey, Tim Purdy, Mike Soukup, and Patricia A. Eliason Proc. SPIE 7014, 701460 (2008); http://dx.doi.org/10.1117/12.787996 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract In 2001, the GONG+ instruments began acquiring solar magnetic field images (magnetograms) every minute. These observations offer a useful resource for the solar physics community. However, the quality of the magnetograms was reduced by a significant zero point error in the observations that varied across the solar image and with time. This precluded using the magnetograms for meaningful extrapolations of weak photospheric fields into the corona. The error was caused by the slow, asymmetric, locally varying switching of the LCD modulator (LCM) from one retardation state to the other. This generated a false magnetic field pattern as a result of different responses to weak instrumental linear polarization ahead of the LCM. The original modulator driver used a very simple design to excite the LCM. Liquid crystals like those in the LCM take different times to switch from one polarization state to the other than to return to the first polarization state. To eliminate the difference in switching times, a driver capable of varying its output during the change in LCM state was needed. A microcontroller-based design was chosen. The final driver design resulted in a factor of 100 improvement in the zero point error.

Select this Article		An EAGLE with arms: a solution to the design of the adaptive multi-IFU spectrograph EAGLE for the E-ELT Robert Content and Peter Hastings Proc. SPIE 7014, 701461 (2008); http://dx.doi.org/10.1117/12.790403 \| Cited 1 time Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract EAGLE is an adaptive multi-IFU spectrograph for the 42-m E-ELT. We present our design of the EAGLE Target Acquisition System (TAS) and IFU system while the spectrograph design is part of a different paper. A modified design of the arms of KMOS, a future multi-IFU spectrograph for the VLT, is used. Their shorter length permits to place more arms in EAGLE than in KMOS. An unusual difficulty in designing the optics was the need for a very high image quality in the pupil images on the deformable mirrors. The solution includes a lens in the arm more complex than in KMOS and a series of mirrors after the arm. The IFU is an Advanced Image Slicer (AIS) with an unusually large anamorphic magnification factor of 3.2. The design makes all IFU fields parallel in the telescope field wherever their positions. Both the anamorphic factor of the AIS and the position of its exit pupil were adjusted to help reduce the size and simplify the design of the spectrograph. The preceding design being our basic design, a different approach that takes advantage of the small field of the main science cases will also be discussed. In this new concept, field selectors permit to have a choice of a large number of small fields or a small number of large fields or a combination of both. Combined with the proper adaptive optics system, the throughput of EAGLE would increase by a factor of more than 2 while maintaining the same cost.

Select this Article		Science requirements for EAGLE for the E-ELT C. J. Evans, M. D. Lehnert, J.-G. Cuby, S. L. Morris, A. M. Swinbank, W. D. Taylor, D. M. Alexander, N. P. F. Lorente, Y. Clénet, and T. Paumard Proc. SPIE 7014, 701462 (2008); http://dx.doi.org/10.1117/12.787797 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present an overview of the EAGLE science case, which spans spatially resolved spectroscopy of targets from five key science areas - ranging from studies of heavily obscured Galactic star clusters, right out to the first galaxies at the highest redshifts. Here we summarise the requirements adopted for the study and also evaluate the availability of natural guide stars in example fields, which will impact on the adaptive optics performance and architecture.

Select this Article		Initial opto-thermal modelling of the EAGLE instrument to maximise SNR performance and resulting design considerations Philippe Laporte, Fanny Chemla, Mathieu Puech, Eric Gendron, Peter Hastings, and Pascal Vola Proc. SPIE 7014, 701463 (2008); http://dx.doi.org/10.1117/12.787832 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract E-ELT will provide a unique opportunity to observe the early universe since its large collecting area will allow detecting faint objects at high redshifts. Primordial galaxies are a key topic for cosmology and for understanding the behaviour of the galaxies in the universe. To achieve these observations, future instruments for the E-ELT will have to provide high sensitivity over a wide range of wavelengths from 1 μm up to 2.5 μm - the upper limit being imposed by the redshift which shifts the OII and Hα lines. For the EAGLE instrument mainly devoted to such observations, we have studied the opto-thermal behaviour of the complete system (TAS - Target Acquisition System - and the spectrograph) to estimate the thermal emission of the optical and the mechanical parts which become a major contributor to the background above 2.2 μm. The nominal operating temperature is a key parameter we must define precisely to both reduce the thermal background and optimise the cooling system in terms of cost and complexity. The results of the simulations show that the TAS and the spectrograph contribute to the thermal background at a similar level and what the optimal temperature should be. We then discuss how such an 'optimal design' might be implemented in practice.

Select this Article		Specifying an MOAO-fed integral field spectrograph for the E-ELT M. Puech, P. Rosati, S. Toft, B. Neichel, and T. Fusco Proc. SPIE 7014, 701465 (2008); http://dx.doi.org/10.1117/12.788713 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present an end-to-end simulator for 3D spectroscopy, which can be used to specify MOAO-fed integral field spectrographs dedicated to ELTs. This simulator re-scales either local data or outputs of hydro-dynamical simulations to model distant galaxies. We present simulations of 3D observations in the H-band, for a rotating disk and a major merger at z=4, and a large range of stellar-mass. We use these simulations to explore the parameter space, focusing on the impact of the telescope diameter, total integration time, spectral resolution, and IFU pixel scale. The size of the telescope diameter has little influence on the spatial resolution of 3D observations but largely influences the achieved SNR. The choice of the IFU pixel scale is driven by the optimal "scale-coupling", i.e., the relation between the spatial resolution of 3D observations and the physical size of the features for which one needs to recover the kinematics using this IFU, and the SNR achieved with this spatial scale. To recover the dynamical state of distant emission line galaxies, one of the main goal of such future instruments, one only needs to recover their large-scale motions, which in turn requires only relatively coarse IFU pixel scales (50-75 mas) and moderate spectral resolution (R=5000).

Select this Article		High contrast imaging feasibility study for FRIDA Mamadou N'Diaye, Salvador Cuevas, and Kjetil Dohlen Proc. SPIE 7014, 701466 (2008); http://dx.doi.org/10.1117/12.787590 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FRIDA will be an Infrared Imager and an Integral Field Spectrograph (IFS) for the 10.4m Gran Telescopio Canarias (GTC). This instrument is scheduled to be installed in 2010, at the Nasmyth A platform of the GTC, behind GTCAO (the Adaptive Optics [AO] system of the GTC). FRIDA design incorporates straightforward upgrade paths for focal plane masks. In this work, we analyze the capability of FRIDA to provide high dynamic range images. Different coronagraphic configurations could be inserted within FRIDA optical assembly. We quantify numerically their performance in presence of AO compensated wavefronts. Thereafter, numerical simulations about the Simultaneous Spectral Differential Imaging¹ (SSDI) method are presented. This technique aims to suppress the AO residual speckles and can be applied to selected frames of the data cube, provided by FRIDA in IFS mode. Therefore, we estimate the starlight attenuation that could be reached with the association "Coronagraph + SSDI method" for the ground-based instrument "GTC + GTCAO + FRIDA".

Select this Article		Multi-stage apodized pupil Lyot coronagraph experimental results L. Abe, M. Venet, K. Enya, H. Kataza, T. Nakagawa, and M. Tamura Proc. SPIE 7014, 701467 (2008); http://dx.doi.org/10.1117/12.787305 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Prolate (Pupil) Apodized Lyot Coronagraphs (PPALC) are known to offer optimal performances for a Lyot-type Coronagraph configuration, i.e. with an opaque occulting focal mask. One additional benefit of PPALC is its possible use in a multi-stage configuration. In theory, the coronagraphic performance can be Q^N, where Q is the energy rejection factor of one stage (the first one), and N the number of stages. Several ground-based telescopes are considering PPALC as an option for their high-contrast instrumentation (e.g. Gemini/GPI, EELT/EPICS, Subaru HiCIAO). Although the PPALC suffers from several limitations, several works are currently focused on fabricating entrance pupil apodizers and trying to find ways to overcome chromatism issues. In this work, we present the first experimental results from Multi-Stage PPALC (MS-PPALC) that was done in the context of the Japanese space telescope SPICA coronagraph project. Our entrance pupil apodizers use small diameter High Energy Beam Sensitive glass (HEBS-glass) from Canyon Materials Inc. The current results show modest coronagraphic performance due to uncompensated phase aberrations inherent to HEBS-glass material. In addition, and due to these uncompensated phase aberrations, the present optical configuration is an altered version of the originally planned set-up. However, we can demonstrate the validity the MS-PPALC concept and compare it to numerical simulations.

Select this Article		Novel dispersive elements for LIRIS Ana B. Fragoso-López, José A. Acosta-Pulido, Elvio Hernández, María Barreto, Antonio Manescau, and Arturo Manchado Proc. SPIE 7014, 701468 (2008); http://dx.doi.org/10.1117/12.786920 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract New dispersive elements providing relative high resolution (R=2200) have been recently incorporated in the near infrared spectrograph LIRIS. These elements are founded on a rather novel design based on a diffractive pattern engraved in fused silica, which is placed between two prisms. These new components are pushing forward the scientific capabilities of the instrument by enhancing the medium resolution spectroscopic mode of operation. Details on the design, specifications and measured performances, as well as aspects related to the integration and astronomical tests in the instrument are presented.

Select this Article		High-efficiency silicon immersion grating by electron-beam lithography Yuji Ikeda, Naoto Kobayashi, Hiroshi Terada, Akinori Shibayama, Akira Ozawa, Chikako Yasui, Sohei Kondo, Tae-Soo Pyo, and Hideyo Kawakita Proc. SPIE 7014, 701469 (2008); http://dx.doi.org/10.1117/12.788126 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Silicon immersion grating have opened the new possibilities of building compact high-resolution cryogenic spectrometers for the near-infrared (NIR) region from 1.4 to 5.5μm. We are developing a silicon immersion grating for a next-generation NIR high-resolution spectrometer attached to the Subaru 8.2 m telescope. Since a long time, the anisotropic wet etching technique using photolithography has used for the fabrication of silicon immersion gratings (e.g., Wiedemann & Jennings1 and Keller et al.2). Here, we present an alternative technique using electron-beam (EB) lithography, which does not employ either any photolithography masks or UV light source. This technique uses "direct" EBs to expose the resist. The EBs are precisely controlled by using a closed-looped system comprising a laser interferometer. As compared to photolithographic technique, this technique results in more accurate groove pitches and lower surface roughness near the edge of the mask. We fabricate a sample grating with a groove pitch of 30 m and a blaze angle of 69° on a 10mm × 20mm × 2mm flat substrate by EB lithography. Our detailed optical testing of the grating using visible laser shows good optical performances: extremely low scattered light (< 0.9%), less production of ghost light (< 0.01%), and high relative diffraction efficiency (~ 88%). We plan to fabricate the final immersion grating by fixing the etched grating substrate to a silicon prism using the optical-contact method. We are in the middle of R&D of this process and found that much tighter optical-contact than usual seems to be required because of the high incidence angle to the contact surface. Our first sample immersion grating shows a significant reflection loss at the contact surface when it is used in an immersion mode with a NIR laser beam. We are trying to improve the polishing process of the thin silicon substrate for better contact.

Select this Article		Silicon immersion grating spectrograph design for the NASA Infrared Telescope Facility A. T. Tokunaga, T. Bond, D. T. Jaffe, M. J. Mumma, J. T. Rayner, E. V. Tollestrup, and D. W. Warren Proc. SPIE 7014, 70146A (2008); http://dx.doi.org/10.1117/12.788253 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present a conceptual design for an innovative infrared cross-dispersed spectrograph for the NASA Infrared Telescope Facility (IRTF) at Mauna Kea. This facility-class instrument will provide a resolving power of up to 80,000 at 1.2-2.5 μm and 67,000 at 3-5 μm with a minimum slit width of 0.25". The instrument employs a silicon immersion grating in order to reduce the size of the instrument. The design incorporates a 2048×2048 infrared array for the spectrograph and an infrared slit viewer. The optical design is optimized for the thermal infrared (2.8-5.5 μm).

Select this Article		Cable tension real-time measure system based on RTLinux Zhiqian Jiang, Lichun Zhu, and Jinwen Hu Proc. SPIE 7014, 70146B (2008); http://dx.doi.org/10.1117/12.790684 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract To meet the need of feed control, Cable Tension Real-time Measure System based on RTLinux was established. And the system is used to keep those cables healthy and safe. Resistance tension sensors are used in the system, and differential holodesmosomes are also used in the system to raise system performance. Bad data checking in software raised the performance of anti-interference.

Select this Article		Investigation of focal ratio degradation in optical fibres for astronomical instrumentation Lisa Crause, Matthew Bershady, and David Buckley Proc. SPIE 7014, 70146C (2008); http://dx.doi.org/10.1117/12.791041 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract A differential method was used to investigate the focal ratio degradation (FRD) exhibited by, and throughput of, a selection of current-generation optical fibres. These fibres were tested to establish which would be best suited to feed the High Resolution Spectrograph being built for the Southern African Large Telescope (SALT), as well as for future instruments on WIYN and SALT. The double re-imaging system of Bershady et al. (2004) was substantially modified to improve image quality and measurement efficiency, and to permit a direct FRD-measurement in the far-field. The re-imaging method compares the beam profile produced by light which passes through a fibre to that which does not. Broad and intermediate band-pass filters were used between 400-800 nm to test for wavelength dependence in the observed FRD over a wide range in beam-speeds. Our results continue to be at odds with a mico-bend model for FRD. We conclude that the new Polymicro FBP fibre is the most suitable product for broadband applications.

Select this Article		Optical design of FRIDA, the integral-field spectrograph and imager for the AO system of the Gran Telescopio Canarias Salvador Cuevas, Stephen S. Eikenberry, Beatriz Sánchez, Oscar Chapa, Carlos Espejo, Rubén Flores-Meza, Gerardo Lara, Luis C. Álvarez, and Carolina Keiman Proc. SPIE 7014, 70146D (2008); http://dx.doi.org/10.1117/12.788024 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS) capabilities with low, intermediate and high spectral resolutions to operate in the wavelength range 0.9 - 2.5 μm. The integral field unit is based on a monolithic image slicer based on the University of Florida FISICA. Both, the imaging mode and IFS observing modes will use the same Rockwell 2K×2K detector. FRIDA will be based at a Nasmyth focus of GTC, behind the GTCAO system. The FRIDA optical design, stray light analysis, tolerance analysis and manufacturing feasibility are described in this contribution.

Select this Article		Experiment of Wide Field Cryogenic Telescope II (WFCT II) at Sutherland, South African Astronomical Observatory Kentaro Haraguchi, Mikio Kurita, Shuji Sato, Weilai Gu, Tetsuya Nagata, Takahiro Nagayama, Takahiro Zenno, and Daisuke Kato Proc. SPIE 7014, 70146E (2008); http://dx.doi.org/10.1117/12.789020 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have developed Wide Field Cryogenic Telescope II (WFCT II) which contains a whole telescope-optics together with a detector in a vacuum case for cooling to suppress thermal emission from a telescope. The telescope inside is a Ritchey-Chretien system with an aperture of 220 mm and a focal length of 1540 mm. Light from celestial objects enters the telescope through a window, hits primary and secondary mirrors, passes through a filter, and reaches a detector. Spiders, baffles, and radiation shields are cooled down to ~80 K or lower by a refrigerator. All the optics reach a low temperature by exchanging heat with the radiation shields. A 1024×1024 InSb infrared array detector covers a field of view of 1 square degree with resolution of 3".5/pixel. The detector is also cooled by the refrigerator and is regulated at 29 ± 0.1 K. WFCT II is mounted on a small equatorial mounting whose size is 1 m in height, 1 m in width, and 1.2 m in length along the N-S direction. The main targets are diffuse emissions radiated from hydrogen atoms, molecules, and carbonaceous materials in star formation regions and the Galactic Center. We have started to obtain scientific data at Sutherland, South African Astronomical Observatory since December 2007.

Select this Article		Calibration and modeling support for instruments at ESO Florian Kerber, Paul Bristow, and Michael R. Rosa Proc. SPIE 7014, 70146F (2008); http://dx.doi.org/10.1117/12.789081 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the activities of the Physical Modeling Group in ESO's Instrumentation Division related to the calibration and physical description of an instrument with the objective to support the data reduction of science data and to facilitate operations. We will use CRIRES and X-shooter as examples to describe the general concept. The core contribution of the group consists of four parts: a) Optical model: describing the configurations of the optical elements of the spectrograph based on engineering information; b) Calibration Reference Data: examples are: Wavelength standards traceable to laboratory standards form the basis for the application of the 2-D wavelength calibration; spectro-photometric standard stars to support flux calibration; physical properties of optical components such as the refractive index (Τ, λ) of a disperser. c) support for Data Reduction Software (DRS) development: simulated data based on a model based description of the instrument; d) general Project Support such as participation in Testing, Commissioning and Science Verification. These tasks have been performed and documented in close collaboration with the project teams and the software development groups. In summary, we have found that the use of instrument physical modeling techniques can be beneficial during all phases of the life of an instrument: design, optimization, manufacture, testing and operations. Once fully integrated in the project plan and scheduling direct and tangible benefits to the overall project result. Hence planning for VLT 2nd generation and E-ELT instruments should make full use of these capabilities.

Select this Article		The COS calibration pipeline and verification process Mary Elizabeth Kaiser, Philip E. Hodge, Charles Keyes, David Sahnow, Thomas Ake, Alessandra Aloisi, Stephane Béland, Rosa Diaz, Scott Friedman, Cynthia Froning, Parviz Ghavamian, James Green, Jason McPhate, Cristina Oliveira, Steve Osterman, et al. Proc. SPIE 7014, 70146G (2008); http://dx.doi.org/10.1117/12.790239 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Cosmic Origins Spectrograph,1 COS, will be installed in the Hubble Space Telescope (HST) during the next servicing mission. This will be the most sensitive ultraviolet spectrograph ever flown aboard the HST. The calibration pipeline (CALCOS), written in Python, has been developed by the Space Telescope Science Institute (STScI) to support the calibration of HST/COS data. As with other HST pipelines, CALCOS uses an association table to specify the data files to be included, and employs header keywords to specify the calibration steps to be performed and the reference files to be used. CALCOS is designed with a common underlying structure for processing far ultraviolet (FUV) and near ultraviolet (NUV) channels which, respectively, use a cross delay line and a Multi Anode Microchannel Array (MAMA) detector. The pipeline basics and channel dependent specifics are presented. The generation and application of the current reference files, derived from ground-based calibration data, is described, along with the pipeline verification process and results. The CALCOS calibration includes pulse-height filtering and geometric correction for the FUV channel; flat-field, deadtime, and Doppler correction for both channels. Methods for obtaining an accurate wavelength calibra-tion using the on-board spectral line lamp are described. The instrument sensitivity is applied to the background corrected spectrum to produce the final flux calibrated spectrum.

Select this Article		The Southern African Large Telescope (SALT) calibration system D. A. H. Buckley, J. Brink, N. S. Loaring, A. Swat, and H. L. Worters Proc. SPIE 7014, 70146H (2008); http://dx.doi.org/10.1117/12.790385 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents details of the instrument calibration system employed on the SALT. It is designed to inject light into the Spherical Aberration Corrector at about the position of the primary mirror caustic, thereby simulating the same degree of vignetting as experienced by celestial objects. A light-shaping diffuser screen, coupled with Fresnel lenses, modifies the beam to increase efficiency and attempt to illuminate the detectors in the same manner as a uniform sky. Light is conveyed by means of liquid light guides from either QTH flat field lamps or a choice of hollow cathode (CuAr, ThAr) and penray (Ar, Hg, Xe, Ne) lamps, used for wavelength calibration. Changing entrance pupil effects are accounted for by employing a moving exit pupil baffle, which can simulate the pupil geometry of a specific track.

Select this Article		Snodar: a new instrument to measure the height of the boundary layer on the Antarctic plateau Colin S. Bonner, Michael C. B. Ashley, Jon S. Lawrence, John W. V. Storey, Daniel M. Luong-Van, and Stuart G. Bradley Proc. SPIE 7014, 70146I (2008); http://dx.doi.org/10.1117/12.788154 \| Cited 2 times Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The height of the atmospheric boundary layer on the Antarctic plateau is of particular importance to designers of optical telescopes for Antarctica. Snodar was developed at the University of New South Wales to measure the height of the atmospheric boundary layer at Dome A and Dome C on the Antarctic plateau. Snodar, or Surface layer Non-Doppler Acoustic Radar, is a true monostatic high-frequency acoustic radar (SODAR) operating between 5 kHz and 15 kHz. As the height of the boundary layer at Dome C is expected to be less then 30 m, and unknown at Dome A, Snodar was designed to have a minimum sampling height of 5 m with a vertical resolution of 1 m or better. Snodar uses a PC/104 computer to perform signal processing in real time, and a USB sound card for low-latency analog IO. Snodar was designed to run autonomously storing data on USB flash disks for retrieval the following summer, while uploading of data acquisition scripts and spot checking of data is possible via Iridium satellite through UNSW's PLATO facility. Snodar also incorporates a unique in-situ calibration sphere. We present details of the design and results from testing of Snodar.

Select this Article		RISE: a fast-readout imager for exoplanet transit timing I. A. Steele, S. D. Bates, N. Gibson, F. Keenan, J. Meaburn, C. J. Mottram, D. Pollacco, and I. Todd Proc. SPIE 7014, 70146J (2008); http://dx.doi.org/10.1117/12.787889 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract By the precise timing of the low amplitude (0.005 - 0.02 magnitude) transits of exoplanets around their parent star it should be possible to infer the presence of other planetary bodies in the system down to Earth-like masses. We describe the design and construction of RISE, a fast-readout frame transfer camera for the Liverpool Telescope designed to carry out this experiment. The results of our commissioning tests are described as well as the data reduction procedure necessary. We present light curves of two objects, showing that the desired timing and photometric accuracy can be obtained providing that autoguiding is used to keep the target on the same detector pixel for the entire (typically 4 hour) observing run.

Select this Article		Hyper Suprime-Cam: back-end electronics for CCD readout Tomohisa Uchida, Hironao Miyatake, Hidehiko Nakaya, Hiroaki Aihara, and Satoshi Miyazaki Proc. SPIE 7014, 70146K (2008); http://dx.doi.org/10.1117/12.788085 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The development status of a prototype readout module for Hyper Suprime-Cam, a next-generation prime-focus camera for the 8.2 m Subaru Telescope, is presented. The camera has a field of view 1.5° in diameter, and produces 2.1 Gbyte of data per exposure. The module transfers the data to computers of a data acquisition system using TCP/IP and Gigabit Ethernet. We have measured the performance of data processing and data transfer of the developed module. The results indicated sufficient performance to read data from all CCDs within the required readout time.

Select this Article		CCCP: a CCD controller for counting photons Olivier Daigle, Jean-Luc Gach, Christian Guillaume, Simon Lessard, Claude Carignan, and Sébastien Blais-Ouellette Proc. SPIE 7014, 70146L (2008); http://dx.doi.org/10.1117/12.788929 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract CCCP, a CCD Controller for Counting Photons, is presented. This new controller uses a totally new clocking architecture and allows to drive the CCD in a novel way. Its design is optimized for the driving of EMCCDs at up to 20MHz of pixel rate and fast vertical transfer. Using this controller, the dominant source of noise of EMCCDs at low flux level and high frame rate, the Clock Induced Charges, were reduced to 0.001 - 0.0018 electron/pixel/frame (depending of the electron multiplying gain), making efficient photon counting possible. CCCP will be deployed in 2009 on the ESO NTT through the 3D-NTT¹ project and on the SOAR through the BTFI project.

Select this Article		The University of Florida's next-generation cryogenic infrared focal plane array controller system Steven N. Raines, Glenn D. Boreman, Stephen S. Eikenberry, Reba M. Bandyopadhyay, and Ismael Quijano Proc. SPIE 7014, 70146M (2008); http://dx.doi.org/10.1117/12.788003 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Infrared Instrumentation Group at the University of Florida has substantial experience building IR focal plane array (FPA) controllers and seamlessly integrating them into the instruments that it builds for 8-meter class observatories, including writing device drivers for UNIX-based computer systems. We report on a design study to investigate implementing an ASIC from Teledyne Imaging Systems (TIS) into our IR FPA controller while simultaneously replacing TIS's interface card with one that eliminates the requirement for a Windows-OS computer within the instrument's control system.

Select this Article		The Dark Energy Survey CCD imager design H. Cease, D. DePoy, G. Derylo, H. T. Diehl, J. Estrada, B. Flaugher, V. Guarino, K. Kuk, S. Kuhlmann, K. Schultz, R. L. Schmitt, A. Stefanik, and A. Zhao Proc. SPIE 7014, 70146N (2008); http://dx.doi.org/10.1117/12.788200 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Dark Energy Survey is planning to use a 3 sq. deg. camera that houses a ~ 0.5m diameter focal plane of 62 2k×4k CCDs. The camera vessel including the optical window cell, focal plate, focal plate mounts, cooling system and thermal controls is described. As part of the development of the mechanical and cooling design, a full scale prototype camera vessel has been constructed and is now being used for multi-CCD readout tests. Results from this prototype camera are described.

Select this Article		Cooling the Dark Energy Camera instrument R. L. Schmitt, H. Cease, D. DePoy, H. T. Diehl, J. Estrada, B. Flaugher, S. Kuhlmann, Birce Onal, and A. Stefanik Proc. SPIE 7014, 70146O (2008); http://dx.doi.org/10.1117/12.786794 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract DECam, camera for the Dark Energy Survey (DES), is undergoing general design and component testing. For an overview see DePoy, et al in these proceedings. For a description of the imager, see Cease, et al in these proceedings. The CCD instrument will be mounted at the prime focus of the CTIO Blanco 4m telescope. The instrument temperature will be 173K with a heat load of 113W. In similar applications, cooling CCD instruments at the prime focus has been accomplished by three general methods. Liquid nitrogen reservoirs have been constructed to operate in any orientation, pulse tube cryocoolers have been used when tilt angles are limited and Joule-Thompson or Stirling cryocoolers have been used with smaller heat loads. Gifford-MacMahon cooling has been used at the Cassegrain but not at the prime focus. For DES, the combined requirements of high heat load, temperature stability, low vibration, operation in any orientation, liquid nitrogen cost and limited space available led to the design of a pumped, closed loop, circulating nitrogen system. At zenith the instrument will be twelve meters above the pump/cryocooler station. This cooling system expected to have a 10,000 hour maintenance interval. This paper will describe the engineering basis including the thermal model, unbalanced forces, cooldown time, the single and two-phase flow model.

Select this Article		Front-end electronics for the Dark Energy Camera (DECam) Laia Cardiel-Sas, Miquel Barceló, Javier Castilla, Juan DeVicente, Dave Huffman, Mark Kozlovsky, Gustavo Martinez, Peter Moore, Jamienson Olsen, Ricardo Schmidt, Terri Shaw, and Walter Stuermer Proc. SPIE 7014, 70146P (2008); http://dx.doi.org/10.1117/12.789671 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Dark Energy Survey Camera (DECam), when completed, is going to have one of the largest existing focal planes, equipped with more than 70 CCDs. Due to the large number of CCDs and the tight space on the camera, the DECam electronics group has developed new compact front-end electronics capable of flexibly and rapidly reading out all the focal plane CCDs. The system is based on the existing MONSOON Image Acquisition System designed by the National Optical Astronomy Observatory (NOAO), and it is currently being used for testing and characterization of CCDs. Boards for the new readout are being developed in USA and Spain, with the first prototypes already produced and tested. The next version with some improvements will be tested during 2008 and the system will be ready for production at the beginning of 2009. Custom MONSOON boards and the electronics path will be described.

Select this Article		Bias selecting in TEXES electronics Andrew J. Kruger, Matthew J. Richter, John H. Lacy, and Britt Holbrook Proc. SPIE 7014, 70146Q (2008); http://dx.doi.org/10.1117/12.789242 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract TEXES is a high resolution mid-infrared spectrograph acting as a visiting instrument at the NASA IRTF and Gemini North telescopes. Switching from high (R=100,000) to medium resolution (R=15,000), the noise becomes detector dominated due to charge cascades in the low-background detector. This is remedied by lowering the bias voltage across the detector, a problem during observing runs as it requires manual adjustment within the electronics. To save telescope time, a bias selector has been created to allow the bias voltage to be switched from the control room between four options. The options were chosen based upon signal to noise vs. bias voltage testing.

Select this Article		Daisy chain expandable readout system for infrared arrays Takahiro Nagayama and Kentaro Haraguchi Proc. SPIE 7014, 70146R (2008); http://dx.doi.org/10.1117/12.789194 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We have developed a control system for infrared array detectors with 16, 32 or more outputs. Our system consists of five boards (clock pattern generator, clock driver, A/D converter, parallel-in, and isolation), and is operated with a Linux (kernel 2.4 or 2.6) PC. It is capable of supplying 24 DC bias voltages and 16 clock voltages, adjustable between -7.5V and +7.5V and the shortest clock width of 156 ns. One A/D board converts 16 analog array outputs to digital data simultaneously using 16 A/D converters. The rms of A/D conversions for fixed voltages is 2-3 ADU (or 150-200 μV) at a sampling rate of 250 kSPS. The parallel-in board has 32 optically isolated input channels, and can receive data from 2 A/D boards simultaneously. The maximum data rate to main memory of PC is 40 MB/sec, corresponding to 20 frames/sec of a 1024×1024 array. Our system is now utilized for Aladdin 2 (InSb, 1024×1024, 32 outputs) of Wide Field Cryogenic Telescope 2 and SB-774 (Si:As, 320×240, 16 outputs) of 17μm Fabry-Perot spectrometer. The A/D boards have daisy-chain capability for next generation arrays with more than 32 outputs. In the daisy-chain mode, all A/D converters are triggered simultaneously, but the A/D boards make time-delayed data transfer. The parallel-in board receives data sequentially by every 32 A/D converters. When we apply our system for 2048×2048 detectors with 64 outputs, the frame rate will be 5 frames/sec.

Select this Article		Design and implementation of an improved chilled water glycol system for NICI array electronics thermal enclosure Gaston Gausachs Proc. SPIE 7014, 70146S (2008); http://dx.doi.org/10.1117/12.790103 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Near Infrared Chronographic Imager (NICI) being commissioned at Gemini was upgraded with a more powerful Chilled Water Glycol System to address early overheating problems. The previous system was replaced with a completely new design favoring improved airflow and increased heat transfer capabilities. The research leading to this upgrade showed a significant lack of cooling power of the original design. The solution was a combination of commercial heat exchanger and fans and a custom built enclosure. As a prime infrared telescope facility, Gemini is very much interested in maintaining the least amount of heat dissipated to the ambient air. The results obtained through the implementation of this solution will be helpful in understanding the state of other existing electronics enclosures as well as those for new instruments to come. With the advent of electronic intensive AO systems, future electronics enclosures must take full advantage of improved cooling. This paper describes the design and implementation phases of the project. The results under maximum operating capacity proved to be within the expected theoretical values and were deemed successful.

Select this Article		The Extreme Polarimeter (ExPo): design of a sensitive imaging polarimeter M. Rodenhuis, H. Canovas, S. V. Jeffers, and C. U. Keller Proc. SPIE 7014, 70146T (2008); http://dx.doi.org/10.1117/12.788439 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Extreme Polarimeter (ExPo) is approaching its first deployment at the 4.2 m William Herschel Telescope at La Palma. This imaging polarimeter, developed at the Astronomical Institute of Utrecht University, aims to study circumstellar material at a contrast ratio with the central star of 10^-9. Working at visible wavelengths, it will provide an inner working angle down to 0.5 arcsec and a field of view of 20 arcsec diameter. ExPo employs a dual beam-exchange technique based on polarimeter designs for solar studies. A partially transmitting coronagraph mask placed in the first focus reduces the light of the star. The beam is modulated using three ferro-electric liquid crystals in a Pancharatnam configuration, then split in a polarizing beamsplitter. Both beams are re-imaged onto the same Electron-Multiplying CCD camera. We present the design of the ExPo instrument, highlighting the elements that are critical to the polarimetric performance. Some prototype laboratory experiments demonstrating the instrument concept are discussed. These have been performed using our realistic exoplanet laboratory simulator.

Select this Article		GFP-IFS: a coronagraphic integral field spectrograph for the APO 3.5-meter telescope David G. Bonfield, Bruce E. Woodgate, Carol A. Grady, George M. Hilton, Larry A. White, and Jacqueline E. McCleary Proc. SPIE 7014, 70146W (2008); http://dx.doi.org/10.1117/12.789558 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design and initial laboratory tests of a new integral-field spectroscopy mode to be added to the Goddard Fabry-Perot instrument at Apache Point Observatory. This new IFS mode incorporates a 'TIGER'-style lenslet array, with pre-optics to allow spatial sampling of 0.21 or 0.42 arcseconds, corresponding to fields-of-view of 7 or 14 arcseconds. For coronography, we insert a mask close to the lenslet array focal plane, blocking a discrete number of the lenslet foci. Three VPH grisms will be available to disperse the spectra, with medium-resolution (R~1000) red (λ ~ 660nm) and green (λ ~ 490nm) modes and a high-resolution (R~5000) red mode. We show that it is possible to reduce crosstalk between spectra by at least an order of magnitude by placing a pinhole mask at the focus of the lenslet array, and present data on the throughput of the lenslets and VPH grism.

Select this Article		ACAM: a new imager/spectrograph for the William Herschel Telescope Chris Benn, Kevin Dee, and Tibor Agócs Proc. SPIE 7014, 70146X (2008); http://dx.doi.org/10.1117/12.788694 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract ACAM will be mounted permanently at a folded-Cassegrain focus of the WHT. It can be used for broad-band or narrow-band optical imaging of an 8.3-arcmin field, or for low-resolution (R ~ 500) spectroscopy. As the only wide-field optical imager at the Cassegrain focus, ACAM is designed to cater for a broad range of science programmes, including those requiring rapid response (e.g. gamma-ray bursts, supernovae) or scheduling at awkward intervals (e.g. successive exoplanet transits), and those requiring the use of many filters (e.g. H_α mapping of low-redshift galaxies). The imaging requirements alone are demanding, requiring a trade-off between field of view (> 8 arcmin), PSF (<< seeing), wavelength coverage (UV to near-IR), throughput (> 0.8) and radius-dependent wavelength shift (< 0.5 nm, for narrow-band filters). We discuss how the trade-off was effected and present the final optical and mechanical design, and the expected performance.

Select this Article		Thermal gradient analysis for the ESOPO spectrograph A. Farah, J. Jesús González, G. Sierra, J. V. Hernández, M. Pedrayes, J. Echevarría, R. Costero, G. Avila, M. Arroyo, F. Cobos, E. Colorado, A. Cordova, O. Chapa, B. Garcia, F. Garfias, et al. Proc. SPIE 7014, 70146Y (2008); http://dx.doi.org/10.1117/12.790213 Online Publication Date: Jul 10, 2008 Full Text: \| Download PDF
	+ -	Show Abstract ESOPO will be a spectrograph of medium resolution for the 2.1 m telescope of the National Observatory at San Pedro Martir, Baja California, Mexico. It has been developed by the Instituto de Astronomia of the Universidad Nacional Autonoma de Mexico (IA-UNAM). The main goal of this instrument is to modernize the capabilities of making science with that particular telescope. It is planned to achieve a spectral resolution between 500 and 5000. ESOPO is split into two arms; each one specialized in a specific wavelength range covering together all the visible light. A very important issue in spectrographs is to avoid inside thermal gradients. Different temperatures in the optical elements produce mechanical movements and image quality degradation during an exposition. The error budget analysis developed for ESOPO allows establishing the required limits for temperature gradients. In this paper is described the thermal analysis of the spectrograph, including specifications, finite element models, thermal equations and expected thermal gradients.

Select this Article		Design, construction, and performance of VIRUS-P: the prototype of a highly replicated integral-field spectrograph for HET Gary J. Hill, Phillip J. MacQueen, Michael P. Smith, Joseph R. Tufts, Martin M. Roth, Andreas Kelz, Joshua J. Adams, Niv Drory, Frank Grupp, Stuart I. Barnes, Guillermo A. Blanc, Jeremy D. Murphy, Werner Altmann, Gordon L. Wesley, Pedro R. Segura, et al. Proc. SPIE 7014, 701470 (2008); http://dx.doi.org/10.1117/12.790235 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the design, construction, and performance of VIRUS-P (Visible Integral-field Replicable Unit Spectrograph - Prototype), the prototype for 150+ identical fiber-fed integral field spectrographs for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). VIRUS-P was commissioned in 2007, is in regular service on the McDonald Observatory 2.7 m Smith telescope, and offers the largest field of any integral field spectrograph. The 246-fiber IFU uses a densepak-type fiber bundle with a 1/3 fill factor. It is fed at f/3.65 through a telecentric, two-group dioptric focal reducer. The spectrograph's double-Schmidt optical design uses a volume phase holographic grating at the pupil between the articulating f/3.32 folded collimator and the f/1.33 cryogenic prime focus camera. High on-sky throughput is achieved with this catadioptric system by the use of high reflectivity dielectric coatings, which set the 340-670 nm bandwidth. VIRUS-P is gimbal-mounted on the telescope to allow short fibers for high UV throughput, while maintaining high mechanical stability. The instrument software and the 18 square arcmin field, fixed-offset guider provide rapid acquisition, guiding, and precision dithering to fill in the IFU field. Custom software yields Poisson noise limited, sky subtracted spectra. The design characteristics are described that achieved uniformly high image quality with low scattered light and fiber-to-fiber cross talk. System throughput exceeds requirements and peaks at 40%. The observing procedures are described, and example observations are given.

Select this Article		Volume phase holographic grating performance on the VIRUS-P instrument Joshua J. Adams, Gary J. Hill, and Phillip J. MacQueen Proc. SPIE 7014, 701471 (2008); http://dx.doi.org/10.1117/12.788242 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Visible Integral-field Replicable Unit Spectrograph Prototype (VIRUS-P) has been in operation on the Harlan J Smith 2.7m Telescope at McDonald Observatory since October of 2006. The prototype was created to test the design and science capabilities of the full VIRUS instrument, wherein 150 copies of the spectrograph will be installed on the Hobby Eberly Telescope (HET). We here discuss the specialized test bench built to assess the blue optimized Volume Phase Holographic (VPH) grating performance. We also give lab and on-telescope efficiency measurements for three such gratings in the wavelength range 3400-6800Å. Two sources of stray light relevant to most spectrograph designs are also discussed.

Select this Article		Mechanical design of VIRUS-P for the McDonald 2.7m Harlan J. Smith Telescope Michael P. Smith, Gary J. Hill, Phillip J. MacQueen, Werner Altmann, John A. Goertz, John M. Good, Pedro R. Segura, and Gordon L. Wesley Proc. SPIE 7014, 701472 (2008); http://dx.doi.org/10.1117/12.789872 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the mechanical and opto-mechanical design for the Prototype Visible Integral-Field Unit Spectrograph (VIRUS-P). The VIRUS-P instrument is the single unit prototype for the planned VIRUS instrument which consists of 192 spectrographs for the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). The VIRUS Prototype is a test bed for the design and will be used for a survey on the McDonald 2.7m Harlan J. Smith Telescope. The mechanical design is driven by the need for high stability. The structure of the instrument is aluminum but the internal optical elements of the collimator and the camera are held in alignment with respect to each other using Invar metering rods. The spectrograph is fiber fed with 246 fibers in a hexagonal packing pattern at the telescope focal plane Integral Field Unit (IFU) and arranged in a slit at the input to the spectrograph. The reverse-Schmidt collimator articulates, and the Volume Phase Holographic (VPH) grating rotates independently relative to the fixed Schmidt camera to allow for versatile grating configurations during the prototype testing. Since the VIRUS spectrograph units will be mounted in a gravity neutral configuration on the HET, the prototype instrument is mounted on a gimbal at the folded cassegrain port of the 2.7m Smith Telescope to negate gravity vector changes.

Select this Article		VIRUS-W: an integral field unit spectrograph dedicated to the study of spiral galaxy bulges Maximilian H. Fabricius, Stuart Barnes, Ralf Bender, Niv Drory, Frank Grupp, Gary J. Hill, Ulrich Hopp, and Phillip J. MacQueen Proc. SPIE 7014, 701473 (2008); http://dx.doi.org/10.1117/12.787204 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the design, layout and performance estimates for a fiber based Integral Field Unit spectrograph. This instrument is built for flexible use at different telescopes, and in particular for the new 2m telescope on Mount Wendelstein in the Bavarian Alps. Based on the VIRUS spectrograph for the HETDEX experiment, the proposed instrument will have a fiber head consisting of 267 optical fibers. The large angular field of view of 150×75 arcseconds will allow full coverage of the bulge regions of most local late type galaxies in one or two pointings. Realized by the usage of VPH gratings, a R ≈ 2500 and a R ≈ 6800 mode with 850Å and 515Å wavelength coverage will be dedicated to the study of stellar populations and kinematics of late type galaxy bulges.

Select this Article		Extreme multiplex spectroscopy at wide-field 4-m telescopes Robert Content and Tom Shanks Proc. SPIE 7014, 701475 (2008); http://dx.doi.org/10.1117/12.790523 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the design and science case for a spectrograph for the prime focus of classical 4-m wide-field telescopes that can deliver at least 4000 MOS slits over a 1° field. This extreme multiplex capability means that 25000 galaxy redshifts can be measured in a single night, opening up the possibilities for large galaxy redshift surveys out to z~0.7 and beyond for the purpose of measuring the Baryon Acoustic Oscillation (BAO) scale and for many other science goals. The design features four cloned spectrographs and exploits the exclusive possibility of tiling the focal plane of wide-field 4-m telescopes with CCDs for multi-object spectroscopic purposes. In ~200 night projects, such spectrographs have the potential to make galaxy redshift surveys of ~6×10⁶ galaxies over a wide redshift range and thus may provide a low-cost alternative to other survey routes such as WFMOS and SKA. Two of these extreme multiplex spectrographs are currently being designed for the AAT (NG1dF) and Calar Alto (XMS) 4-m class telescopes. NG2dF, a larger version for the AAT 2° field, would have 12 clones and at least 12000 slits. The clones use a transparent design including a grism in which all optics are smaller than the clone square subfield so that the clones can be tightly packed with little gaps between the contiguous fields. Only low cost glasses are used; the variations in chromatic aberrations between bands are compensated by changing one or two of the lenses adjacent to the grism. The total weight and length is smaller with a few clones than a unique spectrograph which makes it feasible to place the spectrograph at the prime focus.

Select this Article		Optical-mechanical operation of the F2T2 filter: a tunable filter designed to search for First Light Erin Mentuch, Alan Scott, Roberto Abraham, Elizabeth Barton, Matthew Bershady, Joss Bland-Hawthorn, David Crampton, René Doyon, Steve Eikenberry, Mike Gladders, Karl Glazebrook, Joe Jenson, Jeff Julian, Roger Julian, Jean-Paul Kneib, et al. Proc. SPIE 7014, 701476 (2008); http://dx.doi.org/10.1117/12.789692 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Flamingos-2 Tandem Tunable filter is a tunable, narrow-band filter, consisting of two Fabry-Perot etalons in series, capable of scanning to any wavelength from 0.95 to 1.35 microns with a spectral resolution of R~800. It is an accessory mode instrument for the near-IR Flamingos-2 imaging-spectrograph designed for the Gemini South 8m Observatory and will be fed through the upcoming Multi-Conjugate Adaptive Optics feed. The primary science goal of the F2T2 filter is to perform a ground-based search for the first star forming regions in the universe at redshifts of 7 < z < 11. The construction of the F2T2 filter is complete and it is currently in its calibration and commissioning phases. In this proceeding, we describe the calibration and performance of the instrument.

Select this Article		The Smart Tunable Filter for ELT Olivier Hernandez, Claude Carignan, Philippe Amram, Sebastien Balis-Ouellette, and Benoît Épinat Proc. SPIE 7014, 701477 (2008); http://dx.doi.org/10.1117/12.787398 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Smart Tunable Filter is a new spectrograph providing a continuous field of view of 4'×4' sampled at 56 mas using the technology of imaging Bragg Tunable Filter (BTF) and a scanning Fabry-Perot tunable filter. 48 holographic gratings photoinscripted helicoidally in a doped glass cylinder and preceded by 4 tunable BTF are used to study 52 emission lines selected between the main OH night sky lines. The Smart Tunable Filter offers the advantage to be an "opto-ecological" system providing a complete separation between spectral and spatial information avoiding problems from image slicing and slit effects. The design can fully operate at cryogenic temperatures for IR purpose. The Fabry-Perot mode operates at a spectral resolution of 5000 and can be removed to provide a 100 spectral resolution over the 48 fixed gratings. Main results obtained in laboratory from the first prototype developed in collaboration with Photon etc. Inc. are presented. Merit factors to compare this instrument to similar ones are studied versus sciences cases.

Select this Article		The Carnegie Planet Finder Spectrograph: a status report Jeffrey D. Crane, Stephen A. Shectman, R. Paul Butler, Ian B. Thompson, and Gregory S. Burley Proc. SPIE 7014, 701479 (2008); http://dx.doi.org/10.1117/12.789637 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Carnegie Planet Finder Spectrograph (PFS) has been constructed for use with the Magellan telescopes at Las Campanas Observatory in Chile. PFS has been optimized for high-precision measurement of stellar radial velocities in order to support an ongoing search for extrasolar planets. PFS uses an R4 echelle grating and a prism cross-disperser in a Littrow arrangement to provide complete wavelength coverage between 390 and 620 nm distributed across 58 orders. Spectral resolution is 38,000 when using a 1 arcsec slit. An iodine absorption cell is included in the pre-slit module to allow the superimposition of well-defined absorption features on the stellar spectra. To improve velocity stability, the echelle grating is enclosed in a small vacuum tank with the cross-dispersing prism acting as the vacuum window. The spectrograph is mounted on an invar optical bench that is surrounded by an insulated enclosure with circulating liquid temperature control. Fabrication and assembly have been completed, and testing will soon be underway. Delivery to Las Campanas Observatory is scheduled for late 2008.

Select this Article		Design of a laboratory simulator to test exoplanet imaging polarimetry S. V. Jeffers, N. Miesen, M. Rodenhuis, and C. U. Keller Proc. SPIE 7014, 70147B (2008); http://dx.doi.org/10.1117/12.789275 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Research on extrasolar planets is one of the most rapidly advancing fields of astrophysics. In just over a decade since the discovery of the first extra-solar planet orbiting around 51 Pegasi, 289 extrasolar planets have been discovered. This breakthrough is the result of the development of a wide range of new observational techniques and facilities for the detection and characterisation of extrasolar planets. In Utrecht we are building the Extreme Polarimeter (ExPo) to image extra-solar planets and circumstellar environments using polarimetry at contrast ratio of 10^-9. To test and calibrate ExPo, we have built a laboratory-based simulator that mimics a star with a Jupiter-like exoplanet as seen by the 4.2m William Herschel Telescope. The star and planet are simulated using two single-mode fibres in close proximity that are fed with a broadband arc lamp with a contrast ratio down to 10^-9. The planet is partially linearly polarized. The telescope is simulated with two lenses, and seeing can be included with a rotating glass plate covered with hairspray. In this paper we present the scientific requirements and the simulator design.

Select this Article		Influence of instrumental noise and defocus on the DIMM Z. Benkhaldoun and Y. Hach Proc. SPIE 7014, 70147D (2008); http://dx.doi.org/10.1117/12.789227 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The instrumental noise is an important factor in any measurement. In order to evaluate the amount of seeing introduced by the instrumental noise, we have conducted an experiment using an artificial light source as a star. In addition, we present a study of the defocus effect on the DIMM results. The instrumental noise variance was measured in the laboratory for different states of defocusing. In this paper we will present the results of these various experiments.

Select this Article		LIINUS: a design study for interferometric imaging spectroscopy at the LBT C. Gál, F. Müller-Sánchez, A. Krabbe, F. Eisenhauer, C. Iserlohe, M. Haug, and T. M. Herbst Proc. SPIE 7014, 70147E (2008); http://dx.doi.org/10.1117/12.787771 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present a feasible design concept and the science drivers for the proposed near-infrared interferometric integral field spectrograph at the LBT. Combining interferometric resolution with an integral field spectrograph is a very promising instrument concept for detailed studies down to below 10 mas angular resolution in the NIR. If approved, the instrument will become an extension to the LINC-NIRVANA instrument, which is under construction. In this contribution an opto-mechanical design concept has been studied in detail: that places the integral field unit into an existing empty compartment within the LINC hardware. Several optical and mechanical challenges have been successfully mastered, among them: - the limitation of the achievable angular resolution due to the parallactic angle rotation versus the LBT baseline, - the anamorphic magnification required by the LBT optics design to optimize the detector information content, and - integrating the IFU into the existing LINC cryostat without interfering with the existing optics and mechanics. The science program spans from solar system studies and spectroscopy of exoplanets to the black hole dynamics in the center of our and other galaxies.

Select this Article		Dispersed interferometry for infrared exoplanet velocimetry Jerry Edelstein, Matthew W. Muterspaugh, David Erskine, Mario Marckwordt, W. Michael Feuerstein, Tony Mercer, Agnieszka Czeszumska, Jaclyn Schwer, Sam Halverson, James P. Lloyd, Philip S. Muirhead, Jason T. Wright, and Terry Herter Proc. SPIE 7014, 70147F (2008); http://dx.doi.org/10.1117/12.790315 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The TEDI (TripleSpec - Exoplanet Discovery Instrument) is the first instrument dedicated to the near infrared radial velocity search for planetary companions to low-mass stars. The TEDI uses Externally Dispersed Interferometry (EDI), a combination of interferometry and multichannel dispersive spectroscopy. We have joined a white-light interferometer with the Cornell TripleSpec (0.9 - 2.4 μm) spectrograph at the Palomar Observatory 200" telescope and begun an experimental program to establish both the experimental and analytical techniques required for precision IR velocimetry and the Doppler-search for planets orbiting low mass stars and brown dwarfs.

Select this Article		Gemini helium closed cycle cooling system Manuel Lazo, Ramon Galvez, Rolando Rogers, Hernan Solis, Eduardo Tapia, Diego Maltes, Paul Collins, John White, Chas Cavedoni, Chris Yamasaki, Michael P. Sheehan, and Brian Walls Proc. SPIE 7014, 70147G (2008); http://dx.doi.org/10.1117/12.787736 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Gemini Observatory presents the Helium Closed Cycle Cooling System that provides cooling capacity at cryogenic temperatures for instruments and detectors. It is implemented by running three independent helium closed cycle cooling circuits with several banks of compressors in parallel to continuously supply high purity helium gas to cryocoolers located about 100-120 meters apart. This poster describes how the system has been implemented, the required helium pressures and gas flow to reach cryogenic temperature, the performance it has achieved, the helium compressors and cryocoolers in use and the level of vibration the cryocoolers produce in the telescope environment. The poster also describes the new technology for cryocoolers that Gemini is considering in the development of new instruments.

Select this Article		Optical design of the SCUBA-2 IFTS Melanie R. Leclerc, Brad Gom, and David Naylor Proc. SPIE 7014, 70147I (2008); http://dx.doi.org/10.1117/12.787606 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract An Imaging Fourier Transform Spectrometer (IFTS), named FTS-2, is being developed by the University of Lethbridge for use with the SCUBA-2 sub-millimeter bolometric camera on the James Clerk Maxwell Telescope (JCMT). The FTS-2 optical model was developed and optimized in Zemax by the Institut National d'Optique (INO) to maximize the FOV and efficiency over a range of spectral resolutions. The IFTS has been designed as a folded system including corner cubes in the interferometer moving mirror, and extended polynomial surfaces in the interferometer folding mirrors. The instrument design for FTS-2 is described elsewhere; here we present an analysis of the modeled performance of the IFTS in terms of achievable Field Of View (FOV), spot pattern and vignetting, at Zero Path Difference (ZPD) and for the 2 resolution modes. The predicted imaging performance is compared to that of the SCUBA-2 camera alone.

Select this Article		Technical improvements and performances of SpIOMM: an imaging Fourier transform spectrometer for astronomy Anne-Pier Bernier, Maxime Charlebois, Laurent Drissen, and Frédéric Grandmont Proc. SPIE 7014, 70147J (2008); http://dx.doi.org/10.1117/12.787949 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We present the most recent technical improvements on SpIOMM, an Imaging Fourier Transform Spectrometer (IFTS) attached to the 1.6 telescope of the Mont Megantic Observatory. The recent development of SpIOMM demonstrates that the concept of IFTS for ground telescopes is a promising astronomical 3D spectroscopy technique for multi-object spectroscopy and multi-band imaging. SpIOMM has been developed through a collaboration between Universite Laval and the industry (ABB Bomem). It is designed for optical observations from the near UV (350 nm) to the near IR (850 nm) with variable spectral resolution. The circular FOV of the instrument covers 12' in diameter. We have recently improved the servo system algorithm which now controls the mirror displacement and alignment at a rate of ~7kHz. Hardware improvements to the servo and the metrology system will be described along with their impacts on performance in the laboratory and in observing conditions. The instrument has successfully been operated at the 1.6 meter telescope this year using the revised control systems and acquired several datacubes. We will discuss some issues regarding the sensitivity to environmental conditions implied by the use of such an instrument. An overview of the datacube reduction procedure will show some solutions proposed for observational problems encountered that affect the quality of the data such as sky transmission variations, wind, changing gravity vector and temperature.

Select this Article		Science results from the imaging Fourier transform spectrometer SpIOMM L. Drissen, A.-P. Bernier, M. Charlebois, É. Brière, C. Robert, G. Joncas, P. Martin, and F. Grandmont Proc. SPIE 7014, 70147K (2008); http://dx.doi.org/10.1117/12.787109 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract SpIOMM is an imaging Fourier transform spectrometer designed to obtain the visible range (350 - 850 nm) spectrum of every light source in a circular field of view of 12 arcminutes in diameter. Attached to the 1.6-m telescope of the Observatoire du Mont Megantic in southern Quebec. We present here some results of three successful observing runs in 2007, which highlight SpIOMM's capabilities to map emission line objects over a very wide field of view and a broad spectral range. In particular, we discuss data cubes from the planetary nebula M27, the supernova remnants NGC 6992 and M1, the barred spiral galaxy NGC7479, as well as Stephan's quintet, and interacting group of galaxies.

Select this Article		Current status of the HETDEX fiber optic support system John M. Good, Gary J. Hill, Nicholas T. Mollison, Brian L. Vattiat, Jeremy D. Murphy, Andreas Klez, Martin M. Roth, Phillip J. MacQueen, Marc D. Rafal, Richard D. Savage, Michael P. Smith, and Amanda J. Bayless Proc. SPIE 7014, 70147L (2008); http://dx.doi.org/10.1117/12.790256 \| Cited 1 time Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The Hobby-Eberly Telescope Dark Energy eXperiment [HETDEX] will employ over 43,000 optical fibers to feed light to 192 Visible Integral-Field Replicable Unit Spectrographs [VIRUS]. Each VIRUS instrument is fed by 224 fibers. To reduce cost, the spectrographs are combined into pairs; thus, two bundles of 224 fibers are combined into a single Integral Field Unit [IFU] of 448 fibers. On the input end the fibers are arranged in a square 'dense-pack' array at the HET focal surface. At the output end the IFU terminates in two separate linear arrays which provide entry slits for each spectrometer unit. The IFU lengths must be kept to an absolute minimum to mitigate losses; however, consideration of overall project cost and duration of the science mission have resulted in the generation of two competing concepts. Multiple axes of motion are imposed on the IFUs as they span the shortest distance from the focal surface to each VIRUS unit. Arranging and supporting 96 IFUs, that have a total mass over 450 kg, in a manner that is compatible with these complex translations, together with the management of accompanying forces on the tracking mechanism of the HET, presents a significant technical challenge, which is further compounded by wind buffeting. The longer IFU concept is favored due to overall project cost, but requires tests to assure that the fibers can withstand forces associated with a height differential of 16.25 meters without FRD losses or breakage.

Select this Article		A multi-instrument focal station for a 2m-class robotic telescope Frank Grupp, Florian Lang, Ralf Bender, Claus Gössl, and Ulrich Hopp Proc. SPIE 7014, 70147M (2008); http://dx.doi.org/10.1117/12.788656 \| Cited 2 times Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The design of a multi-instrument Nasmyth port for a 2m class telescope, located near Munich, Germany is presented in this paper. A three channel optical and infrared camera will be located at this Nasmyth focus together with an IFU spectrograph, a high resolution Echelle spectrograph, and a Shack-Hartmann sensor for instrument alignment. Fast switching between the instruments and compact design in a small dome are boundary conditions of the project. Precise guiding and acquisition is made possible for all instruments. Calibration sources are fed to the fiber coupled instruments using a built in telescope simulator.

Select this Article		L-band orthomode transducer for the Sardinia Radio Telescope Alessandro Navarrini and Tonino Pisanu Proc. SPIE 7014, 70147N (2008); http://dx.doi.org/10.1117/12.790557 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract We describe the design, construction, and characterization results of a compact L-band (1.3-1.8 GHz) Orthomode Transducer (OMT) for the Sardinia Radio Telescope (SRT), a 64 m diameter telescope which is being built in the Sardinia island, Italy. The OMT consists of three distinct mechanical parts connected through ultra low loss coaxial cables: a turnstile junction and two identical 180° hybrid power combiners. The turnstile junction is based on a circular waveguide input (diameter of 190 mm,) and on four WR650 rectangular waveguide cavities from which the RF signals are extracted using coaxial probes. The OMT was optimized using a commercial 3D electromagnetic simulator. The main mechanical part of the turnstile junction was machined out of an Aluminum block whose final external shape is a cylinder with diameter 450 mm and height 98 mm. From 1.3 to 1.8 GHz the measured reflection coefficient was less than -22 dB, the isolation between the outputs was less than -45 dB, and the cross polarization was less than -50 dB for both polarization channels.

Select this Article		MONSOON image acquisition system: control techniques for application to the orthogonal transfer array detectors Peter Moore, Nick Buchholz, Mark Hunten, and David Sawyer Proc. SPIE 7014, 70147O (2008); http://dx.doi.org/10.1117/12.802254 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract The MONSOON Detector Controller has successfully demonstrated the ability to control the complex image acquisition and real time processing required to achieve quality science performance from the Orthogonal Transfer Array (OTA) detector technology. A mosaic of four OTA detectors has been used to track multiple guide stars and apply charge shift corrections to compensate for real time image motion. The control algorithms required to achieve this have been embedded and distributed within the MONSOON controller to reduce the control loop latency and improve correction efficiency. This paper highlights the flexibility of the MONSOON architecture in supporting the many roles required by applications of scientific detectors.

Select this Article		A global SOLIS vector spectromagnetograph (VSM) network K. V. Streander, M. S. Giampapa, J. W. Harvey, C. J. Henney, and A. A. Norton Proc. SPIE 7014, 70147P (2008); http://dx.doi.org/10.1117/12.802348 Online Publication Date: Jul 09, 2008 Full Text: \| Download PDF
	+ -	Show Abstract Understanding the Sun's magnetic field related activity is far from complete as reflected in the limited ability to make accurate predictions of solar variability. To advance our understanding of solar magnetism, the National Solar Observatory (NSO) constructed the Synoptic Optical Long-term Investigations of the Sun (SOLIS) suite of instruments to conduct high precision optical measurements of processes on the Sun whose study requires sustained observations over long time periods. The Vector Spectromagnetograph (VSM), the principal SOLIS instrument, has been in operation since 2003 and obtains photospheric vector data, as well as photospheric and chromospheric longitudinal magnetic field measurements. Instrument performance is being enhanced by employing new, high-speed cameras that virtually freeze seeing, thus improving sensitivity to measure the solar magnetic field configuration. A major operational goal is to provide real-time and near-real-time data for forecasting space weather and increase scientific yield from shorter duration solar space missions and ground-based research projects. The National Solar Observatory proposes to build two near-duplicates of the VSM instrument and place them at international sites to form a three-site global VSM network. Current electronic industry practice of short lifetime cycles leads to improved performance and reduced acquisition costs but also to redesign costs and engineering impacts that must be minimized. The current VSM instrument status and experience gained from working on the original instrument is presented herein and used to demonstrate that one can dramatically reduce the estimated cost and fabrication time required to duplicate and commission two additional instruments.

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