SHARK-NIR: challenges and solutions of a high contrast imager alignment

Luca Marafatto; Federico Biondi; Elena Carolo; Gabriele Umbriaco; Maria Bergomi; Marco De Pascale; Davide Greggio; Luigi Lessio; Kalyan Kumar Radhakrishnan Santhakumari; Daniele Vassallo; Valentina Viotto; Jacopo Farinato

doi:10.1117/12.2562329

13 December 2020 SHARK-NIR: challenges and solutions of a high contrast imager alignment

Luca Marafatto, Federico Biondi, Elena Carolo, Gabriele Umbriaco, Maria Bergomi, Marco De Pascale, Davide Greggio, Luigi Lessio, Kalyan Kumar Radhakrishnan Santhakumari, Daniele Vassallo, Valentina Viotto, Jacopo Farinato

Author Affiliations +

Proceedings Volume 11447, Ground-based and Airborne Instrumentation for Astronomy VIII; 1144750 (2020) https://doi.org/10.1117/12.2562329
Event: SPIE Astronomical Telescopes + Instrumentation, 2020, Online Only

Conference Poster

Abstract

SHARK-NIR is a high contrast camera for the LBT, working in Y, J and H bands. It has been conceived and designed to fully exploit the high Strehl adaptive optics correction delivered by the FLAO module, which is being upgraded to SOUL, and will implement different coronagraphic techniques, with contrast as high as 10^-6 up to 65 mas from the star. To maximize the achievable contrast, SHARK-NIR has a couple of peculiar features, namely a fast internal TT loop to minimize the residual jitter and a local NCPA correction, performed through a DM inside the instrument itself. Other than high-contrast imaging, SHARK-NIR also has spectroscopic capabilities, with low and medium resolution, and its relatively wide Field of View (18 x 18 arcsec) makes it accessible to other scientific targets, such as galactic jets and disks, as well as extra-galactic cases. Sharing the focal station with another instrument at LBT (LBTI), the design has been kept very compact. This has been achieved through the use of 4 Off-Axis Parabolic mirrors (OAPs) and three flat folding mirrors able to provide two pupil planes and two focal planes required by the coronagraphic techniques implemented. A mixed optical-mechanical alignment procedure has been identified and extensively simulated using ray-tracing software, demonstrating that the proposed technique converges to the required performance. We report here about the SHARK-NIR lesson learned and status in the frame of the Assembly, Integration and Verification phase (AIV), delayed due to the covid 19 emergency, which is going to finish in first half of 2021 and bringing in this way the first photons to the instrument by the end of 2021.

Citation Download Citation

Luca Marafatto, Federico Biondi, Elena Carolo, Gabriele Umbriaco, Maria Bergomi, Marco De Pascale, Davide Greggio, Luigi Lessio, Kalyan Kumar Radhakrishnan Santhakumari, Daniele Vassallo, Valentina Viotto, and Jacopo Farinato "SHARK-NIR: challenges and solutions of a high contrast imager alignment", Proc. SPIE 11447, Ground-based and Airborne Instrumentation for Astronomy VIII, 1144750 (13 December 2020); https://doi.org/10.1117/12.2562329

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available