Prof. Hirofumi Okita Profile

Prof. Hirofumi Okita

Assistant Professor at Subaru Telescope NAOJ

SPIE Involvement:

Author

Publications (29)

Proceedings Article | 11 September 2024 Presentation + Paper

Presentation + Paper

Design and status overview of TMT telescope structure

Masahiro Sugimoto, Yutaka Ezaki, Kyle Kinoshita, Amir Sadjadpour, Junji Takaki, Yusuke Saruta, Tomoya Hattori, Hayato Hoshino, Yoshihiro Hosokawa, Makoto Endo, Yusuke Sugie, Masaki Haruna, Noboru Kawaguchi, Yasushi Horiuchi, Masaki Tabata, Hiroshi Terada, Seiichi Tazawa, Hirofumi Okita, Koji Omata, Hiroshi Kusumoto, Koichi Okamoto, Masao Saito, Tomonori Usuda

Proceedings Volume 13094, 1309408 (2024) https://doi.org/10.1117/12.3016864

KEYWORDS: Design, Telescopes, Mirrors, Control systems, Prototyping, Thirty Meter Telescope, Earthquakes

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Proceedings Article | 27 August 2024 Poster + Paper

Poster + Paper

ULTIMATE-Subaru: adaptive secondary mirror development status

Shin Oya, Yosuke Minowa, Hirofumi Okita, Yoshito Ono, Hideki Takami

Proceedings Volume 13097, 130975I (2024) https://doi.org/10.1117/12.3018673

KEYWORDS: Telescopes, Adaptive mirrors, Adaptive optics, Turbulence, Design, Actuators, Mirror surfaces, Infrared telescopes, Manufacturing, Deformable mirrors

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Proceedings Article | 27 August 2024 Poster + Paper

Poster + Paper

Subaru laser guide star system upgrade and on-sky characterization

Yosuke Minowa, Yoshito Ono, Yoshiyuki Doi, Yoko Tanaka, Takamasa Bando, Hiroshige Yoshida, Koki Terao, Hirofumi Okita, Matthew Wung, Lucio Ramos, Hajime Ogane, Akimasa Ojika, Masayuki Akiyama

Proceedings Volume 13097, 1309735 (2024) https://doi.org/10.1117/12.3018789

KEYWORDS: Laser guide stars, Telescopes, Laser systems engineering, Relays, Wavefront sensors, Mirrors, Camera shutters, Control systems, Adaptive optics, Stars

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Proceedings Article | 21 August 2024 Presentation + Paper

Presentation + Paper

High-z gamma-ray bursts unraveling the dark ages and extreme space-time mission: HiZ-GUNDAM

Daisuke Yonetoku, Akihiro Doi, Tatehiro Mihara, Hideo Matsuhara, Takanori Sakamoto, Kohji Tsumura, Kunihito Ioka, Makoto Arimoto, Teruaki Enoto, Kenjiro Fujimoto, Hatsune Goto, Shuichi Gunji, Junko Hiraga, Shintaro Ikunaga, Nobuyuki Kawai, Ryuji Kondo, Shunsuke Kurosawa, Junyi Li, Yoshitomo Maeda, Ikuyuki Mitsuishi, Toshio Murakami, Issin Nagataka, Yujin Nakagawa, Naoki Ogino, Taiki Owari, Ryuji Sato, Masataka Sato, Tomoya Sato, Tatsuya Sawano, Motoko Serino, Hsien-Chieh Shen, Satoshi Sugita, Shuta Takahashi, Toru Tamagawa, Keisuke Tamura, Takaaki Tanaka, Toru Tanimori, Makoto Tashiro, Takumi Togashi, Hiroshi Tomida, Keito Watanabe, Kazutaka Yamaoka, Makoto Yamauchi, Yoichi Yatsu, Atsumasa Yoshida, Hiroshi Akitaya, Akihiko Fukui, Haruki Fukui, Yoshifusa Ita, Koji Kawabata, Shuji Matsuura, Akihiro Miyasaka, Kentaro Motohara, Norio Narita, Hirofumi Noda, Hirofumi Okita, Kei Sano, Keisuke Shinozaki, Sou Tajima, Yuji Urata, Takehiko Wada, Kenshi Yanagisawa, Michitoshi Yoshida, Nobutaka Bando, Ichiro Jikuya, Kenji Minesugi, Yasuyuki Miyazaki, Yusuke Kono, Naoki Takase, Shunichi Nakatsubo, Tooru Kaga, Katsuaki Asano, Kohei Inayoshi, Susumu Inoue, Hirotaka Ito, Hideyuki Izumiura, Norita Kawanaka, Tomoya Kinugawa, Shota Kisaka, Kenta Kiuchi, Koutarou Kyutoku, Jin Matsumoto, Akira Mizuta, Kohta Murase, Hiroki Nagakura, Shigehiro Nagataki, Yoshikazu Nakada, Takashi Nakamura, Yuu Niino, Yudai Suwa, Keitaro Takahashi, Takahiro Tanaka, Kenji Toma, Tomonori Totani, Ryo Yamazaki, Jun'ichi Yokoyama, Yuichi Harikane, Masaomi Tanaka, Shigeo Kimura, Mariko Kimura

Proceedings Volume 13093, 1309320 (2024) https://doi.org/10.1117/12.3018571

KEYWORDS: X-rays, Telescopes, Sensors, X-ray telescopes, Satellites, Physics, Near infrared, X-ray astronomy, X-ray imaging

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Proceedings Article | 15 August 2024 Presentation + Paper

Presentation + Paper

Prime Focus Spectrograph (PFS) for Subaru Telescope: progressing final steps to science operation

Naoyuki Tamura, Kiyoto Yabe, Shintaro Koshida, Yuki Moritani, Masayuki Tanaka, Miho Ishigaki, Yuki Ishizuka, Yukiko Kamata, Ali Allaoui, Akira Arai, Stéphane Arnouts, Rudy Barette, Robert Barkhouser, Eddie Bergeron, Patrick Blanchard, Neven Caplar, Michael Carle, Pierre-Yves Chabaud, Yin-Chang Chang, Hsin-Yo Chen, Richard C. Chou, Judith Cohen, Ricardo Costa, Thibaut Crauchet, Rodorigo de Almeida, Antonio de Oliveira, Ligia de Oliveira, Kjetil Dohlen, Leandro dos Santos, László Dobos, Richard Ellis, Steve Ertel, Maximilian Fabricius, Décio Ferreira, Hisanori Furusawa, Wilfred Gee, Javier Garciá-Carpio, Roman Gerasimov, Mirek Golebiowski, Aidan Gray, James Gunn, ChangHoon Hahn, Satoshi Hamano, Randolph Hammond, Albert Harding, Takashi Hattori, Kota Hayashi, Wanqiu He, Timothy Heckman, Stephen Hope, Shu-Fu Hsu, Pin-Jie Huang, Marc Jaquet, Eric Jeschke, Christian Jespersen, Yipeng Jing, Russell Kackley, Jennifer Karr, Satoshi Kawanomoto, Masahiko Kimura, Evan Kirby, Michitaro Koike, Eiichiro Komatsu, Yusei Koyama, Vincent Le Brun, Arnaud Le Fur, David Le Mignant, Gerald Lemson, Yen-Ting Lin, Hung-Hsu Ling, Craig Loomis, Robert Lupton, Fabrice Madec, Danilo Marchesini, Lucas Marrara, Dmitry Medvedev, Sogo Mineo, Arik Mitschang, Satoshi Miyazaki, Kumiko Morihana, Takahiro Morishima, Hitoshi Murayama, Graham Murray, Sakurako Okamoto, Hirofumi Okita, Masato Onodera, Vera Passegger, Joshua Peebles, Paul Price, Tae-Soo Pyo, Lucio Ramos, Daniel Reiley, Martin Reinecke, Mitsuko Roberts, Josemar Rosa, Julien Rousselle, Kody Rubio, Kiaina Schubert, Michael Seiffert, Jared Siegel, Stephen Smee, Laerte Sodré, Michael Strauss, Tomomi Sunayama, Christian Surace, Masahiro Takada, Yuhei Takagi, Ichi Tanaka, Yoko Tanaka, Aniruddha Thakar, Didier Vibert, Shiang-Yu Wang, Chih-Yi Wen, Suzanne Werner, Matthew Wung, Chi-Hung Yan, Naoki Yasuda, Hiroshige Yoshida

Proceedings Volume 13096, 1309605 (2024) https://doi.org/10.1117/12.3015967

KEYWORDS: Telescopes, Equipment, Engineering, Cameras, Calibration, Observatories, Stars, Near infrared, Observational astronomy, Spectrographs

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The instrumentation of the Prime Focus Spectrograph (PFS), a next generation facility instrument on the Subaru telescope, is now in the final phase of its commissioning process and its general, open-use operations for sciences will provisionally start in 2025. The instrument enables simultaneous spectroscopy with 2386 individual fibers distributed over a very wide (∼1.3 degrees in diameter) field of view on the Subaru’s prime focus. The spectra cover a wide range of wavelengths from 380nm to 1260nm in one exposure in the Low-Resolution (LR) mode (while the visible red channel has the Medium-Resolution (MR) mode as well that covers 710−885nm). The system integration activities at the observatory on Maunakea in Hawaii have been continuing since the arrival of the Metrology Camera System in 2018. On-sky engineering tests and observations have also been carried out continually since September 2021 and, despite various difficulties in interlacing commissioning processes with development activities on the schedule and addressing some major issues on hardware and software, the team successfully observed many targeted stars as intended over the entire field of view (Engineering First Light) in September 2022. Then in parallel to the arrival, integration and commissioning of more hardware components, validations and optimizations of the performance and operation of the instrument are ongoing. The accuracy of the fiber positioning process and the speed of the fiber reconfiguration process have been recently confirmed to be ∼ 20−30μm for 95% of allocated fibers, and ∼130 seconds, respectively. While precise quantitative analyses are still in progress, the measured throughput has been confirmed to be consistent with the model where the information from various sub-components and sub-assemblies is integrated. Long integration of relatively faint objects are being taken to validate an expected increase of signal-to-noise ratio as more exposures are taken and co-added without any serious systematic errors from, e.g., sky subtraction process. The PFS science operation will be carried out in a queue mode by default and various developments, implementations and validations have been underway accordingly in parallel to the instrument commissioning activities. Meetings and sessions are arranged continually with the communities of potential PFS users on multiple scales, and discussions are iterated for mutual understanding and possible optimization of the rules and procedures over a wide range of processes such as proposal submission, observation planning, data acquisition and data delivery. The end-to-end processes of queue observations including successive exposures with updated plans based on assessed qualities of the data from past observations are being tested during engineering observations, and further optimizations are being undertaken. In this contribution, a top-level summary of these achievements and ongoing progresses and future perspectives will be provided.

Proceedings Article | 5 August 2024 Presentation + Paper

Presentation + Paper

Project overview and update on ULTIMATE-Subaru: the next-generation wide-field AO instrument for the Subaru telescope

Yosuke Minowa, Yusei Koyama, Masayuki Akiyama, Sadman Ali, Takamasa Bando, Joshua Carter, David Chandler, Chi-Yi Chou, Jesse Cranney, Celine D'Orgeville, Yutaka Hayano, Takashi Hattori, Roger Haynes, Dionne Haynes, Angela Hernandez Delgado, Nicholas Herrald, Masayuki Hirabayashi, Junichi Katakura, Masahiko Kimura, Tadayuki Kodama, Masahiro Konishi, Andrew Kruse, Noelia Martinez Rey, Kumiko Morihana, Masaki Morita, Kentaro Motohara, Yoshiyuki Obuchi, Hajime Ogane, Hirofumi Okita, Yoshito Ono, Shin Oya, Naohisa Sato, Yuhei Takagi, Hideki Takami, Ichi Tanaka, Yoko Tanaka, Koki Terao, Chihiro Tokoku, Fumihiro Uraguchi, Lu Wang, Shiang-Yu Wang, Kenshi Yanagisawa, Hiroshige Yoshida, Michitoshi Yoshida

Proceedings Volume 13096, 130961A (2024) https://doi.org/10.1117/12.3018698

KEYWORDS: Telescopes, Equipment, Wavefront sensors, Design, Adaptive optics, Near infrared, Imaging systems, Spectrographs, Prototyping, Sensors

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Proceedings Article | 19 July 2024 Presentation

Presentation

Instrumentation at the Subaru Telescope

Takashi Hattori, Naoyuki Tamura, Yosuke Minowa, Hirofumi Okita, Julien Rousselle

Proceedings Volume 13096, 1309602 (2024) https://doi.org/10.1117/12.3019200

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Proceedings Article | 18 July 2024 Poster + Paper

Poster + Paper

Prime Focus Spectrograph (PFS) for Subaru Telescope: performance verification of the science-grade fiber optics cable

Shintaro Koshida, Yuki Moritani, Julien Rousselle, Matthew Wung, Hirofumi Okita, Ligia Souza de Oliveira, Décio Ferreira, Antonio Cesar de Oliveira, Graham Murray, Naoyuki Tamura

Proceedings Volume 13096, 130962O (2024) https://doi.org/10.1117/12.3019412

KEYWORDS: Telescopes, Connectors, Transmittance, Spectrographs, Fiber science, Fiber optics, Air temperature, Light sources, Light emitting diodes, Signal intensity

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We present the results of optical performance verification for the Prime Focus Spectrograph (PFS) fiber optics module, so-called “CableBs”, at Subaru Telescope. PFS is the next generation ultra-wide field multi object spectrograph. It employs 2386 fibers of which the fiber tips are placed precisely on the primary focal plane over a field of view of 1.3 degrees in diameter. CableB transfers light from the fiber positioning module, or Prime Focus Instrument, to the spectrographs. PFS utilizes four CableBs and each of them carries just over 600 science grade fibers. We completed installation of all CableBs at the telescope in June 2023 after two-years of intermittent work. The optical performance of each CableB was subsequently assessed, focusing on four areas; continuity, uniformity, throughput, and focal ratio degradation (FRD). For examining continuity, we illuminated one termination of CableB with flat LED panel and observed the transmitted light. We found only one fiber newly broken during shipment from the integration site. We also checked uniformity of the relative intensity of light propagating in each fiber. The whole variations around the average intensities fit in 20% range among fibers in each CableB, which was consistent with the measurement before shipping. Throughput of sampled fibers were measured in a wavelength range from 400 to 1400 nm with commercial spectrometers. The measurement at the telescope and the integration site each showed a throughput of approximately 70%, so both sets of measurements are consistent. Finally, we measured FRD employing the collimated beam method to ensure that CableBs were free from any significant physical stress after the installation. Our FRD measurements were comparable before and after the installation. In addition, a long-term monitoring of over a few months showed FRD remained sufficiently stable for science operations. According to these results, we conclude that the installation of CableBs at Subaru Telescope was successful.

SPIE Journal Paper | 4 March 2024 Open Access

Open Access

Development of a near-infrared wide-field integral field unit by ultra-precision diamond cutting

Kosuke Kushibiki, Shinobu Ozaki, Masahiro Takeda, Takuya Hosobata, Yutaka Yamagata, Shin-ya Morita, Toshihiro Tsuzuki, Keiichi Nakagawa, Takao Saiki, Yutaka Ohtake, Kenji Mitsui, Hirofumi Okita, Yutaro Kitagawa, Yukihiro Kono, Kentaro Motohara, Hidenori Takahashi, Masahiro Konishi, Natsuko Kato, Shuhei Koyama, Nuo Chen

JATIS, Vol. 10, Issue 01, 015004, (March 2024) https://doi.org/10.1117/12.10.1117/1.JATIS.10.1.015004

KEYWORDS: Mirrors, Telescopes, Image quality, Mirror surfaces, Vignetting, Surface roughness, Engineering, Stars, Optical components, Off axis mirrors

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Proceedings Article | 30 August 2022 Poster + Presentation + Paper

Poster + Presentation + Paper

ULTIMATE-Subaru: adaptive secondary mirror system

Shin Oya, Yosuke Minowa, Hirofumi Okita, Yoshito Ono, Christophe Clergeon

Proceedings Volume 12185, 121857T (2022) https://doi.org/10.1117/12.2629788

KEYWORDS: Telescopes, Mirrors, Adaptive optics, Calibration, Optical design, Light sources, Interfaces

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Proceedings Article | 30 August 2022 Presentation + Paper

Presentation + Paper

ULTIMATE-Subaru: GLAO preliminary design overview

Yosuke Minowa, Yoshito Ono, Yoko Tanaka, Hiroshige Yoshida, Koki Terao, Yusei Koyama, Sadman Ali, Ichi Tanaka, Takashi Hattori, Hirofumi Okita, Yutaka Hayano, Shin Oya, Kentaro Motohara, Kenshi Yanagisawa, Michitoshi Yoshida, Masayuki Akiyama, Tadayuki Kodama, Hajime Ogane, Masahiro Konishi, Noelia Martinez Rey, Nicholas Herrald, Céline d'Orgeville, François Rigaut, Israel Vaughn, David Chandler, Dionne Haynes, Warrick Schofield, Shiang-Yu Wang, Chi-Yi Chou, Masahiko Kimura

Proceedings Volume 12185, 1218521 (2022) https://doi.org/10.1117/12.2629749

KEYWORDS: Telescopes, Mirrors, Control systems, Stars, Camera shutters, Adaptive optics, Wavefront sensors, Optical instrument design, Near infrared, Monochromatic aberrations

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Proceedings Article | 29 August 2022 Poster + Paper

Poster + Paper

Development status of a near-infrared integral field unit SWIMS-IFU

Kosuke Kushibiki, Shinobu Ozaki, Masahiro Takeda, Takuya Hosobata, Yutaka Yamagata, Shinya Morita, Keiichi Nakagawa, Takao Saiki, Yutaka Ohtake, Toshihiro Tsuzuki, Kenji Mitsui, Hirofumi Okita, Kentaro Motohara, Hidenori Takahashi, Masahiro Konishi, Natsuko M. Kato, Shuhei Koyama, Nuo Chen, Shogo Homan, Akino Yasuda

Proceedings Volume 12188, 121882V (2022) https://doi.org/10.1117/12.2627205

KEYWORDS: Mirrors, Image quality, Vignetting, Optical fabrication, Stray light, Fabrication, Tolerancing, Surface roughness

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Proceedings Article | 29 August 2022 Presentation + Paper

Presentation + Paper

Prime Focus Spectrograph (PFS) for the Subaru Telescope: its start of the last development phase

Naoyuki Tamura, Yuki Moritani, Kiyoto Yabe, Yuki Ishizuka, Yukiko Kamata, Ali Allaoui, Akira Arai, Stéphane Arnouts, Robert Barkhouser, Rudy Barette, Patrick Blanchard, Eddie Bergeron, Neven Caplar, Pierre-Yves Chabaud, Yin-Chang Chang, Hsin-Yo Chen, Chueh-Yi Chou, You-Hua Chu, Judith Cohen, Richardo da Costa, Thibaut Crauchet, Rodrigo de Almeida, Antonio de Oliveira, Ligia de Oliveira, Kjetil Dohlen, Leandro dos Santos, Richard Ellis, Maximilian Fabricius, Décio Ferreira, Hisanori Furusawa, Jahmour Givans, Javier Garciá-Carpio, Mirek Golebiowski, Aidan Gray, James Gunn, Satoshi Hamano, Randolph Hammond, Albert Harding, Kota Hayashi, Wanqiu He, Timothy Heckman, Stephen Hope, Shu-Fu Hsu, Yen-Shan Hu, Pin Jie Huang, Miho Ishigaki, Eric Jeschke, Yipeng Jing, Erin Kado-Fong, Jennifer Karr, Satoshi Kawanomoto, Masahiko Kimura, Michitaro Koike, Eiichiro Komatsu, Shintaro Koshida, Vincent Le Brun, Arnaud Le Fur, David Le Mignant, Romain Lhoussaine, Yen-Ting Lin, Hung-Hsu Ling, Craig Loomis, Robert Lupton, Fabrice Madec, Danilo Marchesini, Edouard Marguerite, Lucas Marrara, Dmitry Medvedev, Sogo Mineo, Satoshi Miyazaki, Takahiro Morishima, Kazumi Murata, Hitoshi Murayama, Graham Murray, Hirofumi Okita, Masato Onodera, Joshua Peebles, Paul Price, Tae-Soo Pyo, Lucio Ramos, Daniel Reiley, Martin Reinecke, Mitsuko Roberts, Josimar Rosa, Julien Rousselle, Mira Sarkis, Michael Seiffert, Kiaina Schubert, Hassan Siddiqui, Stephen Smee, Laerte Sodré, Michael Strauss, Christian Surace, Manuchehr Taghizadeh Popp, Philip Tait, Masahiro Takada, Yuhei Takagi, Masayuki Tanaka, Yoko Tanaka, Aniruddha Thakar, Didier Vibert, Shiang-Yu Wang, Chih-Yi Wen, Suzanne Werner, Matthew Wung, Gerald Lemson, Arik Mitschang, Naoki Yasuda, Hiroshige Yoshida, Chi-Hung Yan, Michitoshi Yoshida, Takuji Yamashita

Proceedings Volume 12184, 1218410 (2022) https://doi.org/10.1117/12.2628152

KEYWORDS: Telescopes, Cameras, Spectrographs, Optical fibers, Observatories, Sensors, Astronomy, Software development, Near infrared, Connectors

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Proceedings Article | 29 August 2022 Presentation + Paper

Presentation + Paper

Instrumentation at the Subaru Telescope

Takashi Hattori, Yosuke Minowa, Hirofumi Okita, Julien Rousselle, Michitoshi Yoshida

Proceedings Volume 12184, 1218402 (2022) https://doi.org/10.1117/12.2629780

KEYWORDS: Telescopes, Spectrographs, Adaptive optics, Imaging systems, Cameras, Near infrared, Laser guide stars, Astronomical imaging, Wavefront sensors, Astronomy

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Proceedings Article | 10 March 2021 Presentation + Paper

Presentation + Paper

Prime Focus Spectrograph (PFS) for the Subaru telescope: a next-generation facility instrument of the Subaru telescope has started coming

Naoyuki Tamura, Naruhisa Takato, Yuki Moritani, Kiyoto Yabe, Yuki Ishizuka, Yukiko Kamata, Ali Allaoui, Stéphane Arnouts, Robert Barkhouser, Philippe Balard, Rudy Barette, Mohamed Belhadi, Jill Burnham, Neven Caplar, Michael Carr, Pierre-Yves Chabaud, Yin-Chang Chang, Hsin-Yo Chen, Richard Chou, You-Hua Chu, Judith Cohen, Ricardo Costa, Thibaut Crauchet, Rodrigo de Almeida, Antonio de Oliveira, Ligia de Oliveira, Kjetil Dohlen, Leandro dos Santos, Richard Ellis, Maximilian Fabricius, Décio Ferreira, Hisanori Furusawa, Javier Garcia-Carpio, Mirek Golebiowski, Aidan Gray, James Gunn, Albert Harding, Randolph Hammond, Murdock Hart, Timothy Heckman, Stephen Hope, Shu-Fu Hsu, Yen-Sang Hu, Pin-Jie Huang, Marc Jaquet, Eric Jeschke, Yipeng Jing, Erin Kado-Fong, Jennifer Karr, Satoshi Kawanomoto, Masahiko Kimura, Michitaro Koike, Eiichiro Komatsu, Shintaro Koshida, Vincent Le Brun, Olivier Le Fèvre, Arnaud Le Fur, David Le Mignant, Hung-Hsu Ling, Craig Loomis, Robert Lupton, Fabrice Madec, Danilo Marchesini, Edouard Marguerite, Lucas Marrara, Dmitry Medvedev, Sogo Mineo, Hitoshi Murayama, Graham Murray, Youichi Ohyama, Hirofumi Okita, Yuki Okura, Masato Onodera, Joseph Orndorff, Sandrine Pascal, Joshua Peebles, Lucio Ramos, Daniel Reiley, Martin Reinecke, Mitsuko Roberts, Josimar Rosa, Julien Rousselle, Mira Sarkis, Alain Schmitt, Michael Seiffert, Kiaina Schubert, Hassan Siddiqui, Stephen Smee, Laerte Sodré, Michael Strauss, Christian Surace, Manuchehr Taghizadeh-Popp, Philip Tait, Masahiro Takada, Satoshi Takita, Tomonori Tamura, Masayuki Tanaka, Yoko Tanaka, Aniruddha Thakar, Didier Vibert, Shiang-Yu Wang, Chih-Yi Wen, Suzanne Werner, Matthew Wung, Yoshihiko Yamada, Takuji Yamashita, Chi-Hung Yan, Naoki Yasuda, Hiroshige Yoshida, Michitoshi Yoshida

Proceedings Volume 11447, 1144713 (2021) https://doi.org/10.1117/12.2562206

KEYWORDS: Spectrographs, Telescopes, Cameras, Imaging systems, Multiplexing, Optical fibers, Hardware testing, Metrology, Observatories, Visible radiation

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Proceedings Article | 13 December 2020 Presentation + Paper

Presentation + Paper

Development of an optical and near-infrared telescope onboard the HiZ-GUNDAM mission

Kohji Tsumura, Daisuke Yonetoku, Koji Kawabata, Shuji Matsuura, Hirofumi Noda, Yuji Urata, Yuu Niino, Kei Sano, Akisato Ohashi, Akihiro Doi, Hiroshi Akitaya, Akihiro Miyasaka, Miku Kurimata, Yoshikatsu Kawata, Makoto Arimoto, Hirofumi Okita

Proceedings Volume 11443, 114430R (2020) https://doi.org/10.1117/12.2560654

KEYWORDS: Telescopes, Infrared telescopes, Optical instrument design, X-ray telescopes, Astronomy, Gamma radiation, X-rays, Satellites, Infrared detectors, Mirrors

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Proceedings Article | 13 December 2020 Poster + Paper

Poster + Paper

The University of Tokyo Atacama Observatory 6.5m telescope: On-sky performance of the near-infrared instrument SWIMS on the Subaru telescope

Masahiro Konishi, Kentaro Motohara, Hidenori Takahashi, Natsuko Kato, Kosuke Kushibiki, Hiroki Nakamura, Nuo Chen, Tadayuki Kodama, Masao Hayashi, Ichi Tanaka, Ken-ichi Tadaki, Jun Toshikawa, Yusei Koyama, Rhythm Shimakawa, Tomoko Suzuki, Tetsuro Asano, Hirofumi Okita, Shintaro Koshida, Ken Tateuchi, Soya Todo, Yutaka Kobayakawa, Yutaro Kitagawa, Hirofumi Ohashi, Yukihiro Kono, Yasunori Terao, Tsutomu Aoki, Kentaro Asano, Mamoru Doi, Bunyo Hatsukade, Takafumi Kamizuka, Kotaro Kohno, Takeo Minezaki, Takashi Miyata, Tomoki Morokuma, Mizuki Numata, Shigeyuki Sako, Hiroaki Sameshima, Takao Soyano, Toshihiko Tanabé, Masuo Tanaka, Ken'ichi Tarusawa, Ryou Ohsawa, Kengo Tachibana, Tsubasa Michifuji, Yuzuru Yoshii

Proceedings Volume 11447, 114475H (2020) https://doi.org/10.1117/12.2560422

KEYWORDS: Telescopes, Observatories, Infrared telescopes, Astronomical imaging, Infrared spectroscopy, Infrared radiation, Spectrographs, Mirrors, Imaging spectroscopy, Spectroscopes

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Proceedings Article | 13 December 2020 Poster + Presentation + Paper

Poster + Presentation + Paper

The real throughput: Site plus optics plus in-situ cleaning for an optical-IR telescope

Saeko Hayashi, Hirofumi Okita, Eric Hansen, Angel Otarola, Takuya Yamashita, Shin Oya, Tomonori Usuda

Proceedings Volume 11445, 114456P (2020) https://doi.org/10.1117/12.2557897

KEYWORDS: Telescopes, Reflectivity, Coating, Atmospheric optics, Scattering, Contamination, Ultraviolet radiation, Astronomy, Astronomical telescopes, Photons

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Proceedings Article | 13 December 2020 Paper

Paper

Instrumentation at the Subaru Selescope

Takashi Hattori, Naruhisa Takato, Yosuke Minowa, Hirofumi Okita

Proceedings Volume 11447, 1144702 (2020) https://doi.org/10.1117/12.2561962

KEYWORDS: Imaging systems, Adaptive optics, Computing systems, Spectrographs, Telescopes, Metrology, Cameras, Infrared imaging, Thermography, Infrared radiation

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Proceedings Article | 13 December 2020 Poster + Paper

Poster + Paper

In-situ monitoring of Subaru Telescope’s optical performance using a portable spectrophotometer

Hirofumi Okita, Hiroyuki Iwashita, Tatsuhiro Sato, Saeko Hayashi, Naruhisa Takato

Proceedings Volume 11451, 114515J (2020) https://doi.org/10.1117/12.2562057

KEYWORDS: Reflectivity, Telescopes, Spectrophotometry, Mirrors, Silver, Surface plasmons, Visible radiation, Reflector telescopes, Data modeling, Infrared radiation

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Proceedings Article | 13 December 2020 Poster + Paper

Poster + Paper

Effect of the lack of the windscreen at Subaru Telescope

Hirofumi Okita, Tsuyoshi Terai, Olivier Guyon, Naruhisa Takato, Hideki Takami

Proceedings Volume 11445, 114455Y (2020) https://doi.org/10.1117/12.2562093

KEYWORDS: Telescopes, Stars, Mirrors

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Proceedings Article | 13 December 2020 Presentation + Paper

Presentation + Paper

High-redshift gamma-ray burst for unraveling the Dark Ages Mission: HiZ-GUNDAM

Daisuke Yonetoku, Tatehiro Mihara, Akihiro Doi, Takanori Sakamoto, Kohji Tsumura, Kunihito Ioka, Yusuke Amaya, Makoto Arimoto, Teruaki Enoto, Takeru Fujii, Hatsune Goto, Shuichi Gunji, Junko Hiraga, Hirokazu Ikeda, Nobuyuki Kawai, Shunsuke Kurosawa, Jin Li, Yoshitomo Maeda, Ikuyuki Mitsuishi, Toshio Murakami, Yujin Nakagawa, Naoki Ogino, Masanori Ohno, Tatsuya Sawano, Kensyo Sei, Motoko Serino, Satoshi Sugita, Toru Tamagawa, Keisuke Tamura, Takaaki Tanaka, Toru Tanimori, Makoto Tashiro, Hiroshi Tomida, Hyeongsoon Wang, Tomohiro Yamaguchi, Ayumi Yamamoto, Kazutaka Yamaoka, Makoto Yamauchi, Yoichi Yatsu, Atsumasa Yoshida, Daito Yuhi, Hiroshi Akitaya, Akihiko Fukui, Yoshifusa Ita, Hidehiro Kaneda, Koji Kawabata, Yoshikatsu Kawata, Miku Kurimata, Toshio Matsumoto, Shuji Matsuura, Akihiro Miyasaka, Kentaro Motohara, Norio Narita, Hirofumi Noda, Akisato Ohashi, Hirofumi Okita, Kei Sano, Masaomi Tanaka, Yuji Urata, Takehiko Wada, Hikaru Yamaguchi, Kenshi Yanagisawa, Michitoshi Yoshida, Katsuaki Asano, Kohei Inayoshi, Susumu Inoue, Hirotaka Ito, Hideyuki Izumiura, Norita Kawanaka, Tomoya Kinugawa, Shota Kisaka, Kenta Kiuchi, Jin Matsumoto, Akira Mizuta, Kohta Murase, Hiroki Nagakura, Shigehiro Nagataki, Yoshikazu Nakada, Takashi Nakamura, Yuu Niino, Yudai Suwa, Keitaro Takahashi, Takahiro Tanaka, Kenji Toma, Tomonori Totani, Ryo Yamazaki, Jun'ichi Yokoyama

Proceedings Volume 11444, 114442Z (2020) https://doi.org/10.1117/12.2560603

KEYWORDS: Gamma radiation, Astronomy, X-ray optics, Satellite communications, Satellites, Observatories, X-ray detectors, X-ray telescopes, X-ray imaging, X-rays

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SPIE Journal Paper | 22 January 2019 Open Access

Open Access

Subaru Portable Spectrophotometer: in-situ reflectivity measurement for large telescope mirror

Hirofumi Okita, Naruhisa Takato, Saeko S. Hayashi

JATIS, Vol. 5, Issue 01, 014002, (January 2019) https://doi.org/10.1117/12.10.1117/1.JATIS.5.1.014002

KEYWORDS: Reflectivity, Mirrors, Surface plasmons, Telescopes, Reflector telescopes, Spectroscopy, Spectrophotometry, Light sources, Integrating spheres, Calibration

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SPIE Journal Paper | 12 September 2018 Open Access

Open Access

Characterizing vibrations at the Subaru Telescope for the Subaru coronagraphic extreme adaptive optics instrument

Julien Lozi, Olivier Guyon, Nemanja Jovanovic, Naruhisa Takato, Garima Singh, Barnaby Norris, Hirofumi Okita, Takamasa Bando, Frantz Martinache

JATIS, Vol. 4, Issue 04, 049001, (September 2018) https://doi.org/10.1117/12.10.1117/1.JATIS.4.4.049001

KEYWORDS: Telescopes, Coronagraphy, Computer programming, Adaptive optics, Image quality, Device simulation, Imaging systems, Mirrors, Point spread functions, Wavefront sensors

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Proceedings Article | 10 July 2018 Presentation + Paper

Presentation + Paper

In-situ measurement of the Subaru Telescope primary mirror reflectivity

Hirofumi Okita, Naruhisa Takato, Saeko Hayashi

Proceedings Volume 10706, 107061U (2018) https://doi.org/10.1117/12.2311899

KEYWORDS: Reflectivity, Mirrors, Telescopes, Reflector telescopes, Spectroscopy, Spectrophotometry

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The reflectivity of telescope primary mirror is one of the fundamental parameters that shows the telescope performance. However, it has been difficult to obtain absolute value, especially the wide range spectroscopic performance measured in-situ on the primary mirror due to the lack of suitable measuring instrument. To overcome this challenge, we developed a portable spectrophotometer to measure the absolute spectroscopic reflectivity of telescope primary mirror. Its small dimension and light weight enable in-situ measurement on the primary mirror. This spectrophotometer covers the spectral range from 380 nm to 1000 nm with 2 nm resolution. The incident angle to the measuring surface is 12 degrees. The measurement beam size is about 12 mm in diameter. To obtain the absolute value, we adopted the principle of V-N method for the spectrophotometer. A sequential measurement also enables us to cancel the instability of the instrument.

The Subaru Telescope primary mirror was recoated with Aluminum on October 20, 2017. It was the eighth coating work from its arrival at Maunakea, Hawaii in 1998 and was about four years from the previous recoating. Before the recoating work, the reflectivity measured with the spectrophotometer was 70~76 % (@400 nm), 75~80 % (@600 nm), and 73~78 % (@800 nm). The large dispersion of the reflectivity is from non-uniform contamination of the surface, especially from the accumulation of dust particles on the mirror.

After the fresh coating of Aluminum, the values returned to 92.1 % (@400 nm), 90.5 % (@600 nm), and 85.8 % (@800 nm) with standard deviation less than 0.6 %. There were the data taken at the outside of the vacuum chamber right after the recoating.

The great advantage of our spectrophotometer is its capability of getting absolute spectroscopic reflectivity of the primary mirror in-situ. We can continue to monitor the reflectivity of the primary mirror in-situ using this spectrophotometer, even after the primary mirror is mounted on the telescope. This helps us better understanding of the long-term reflectivity degradation.

Proceedings Article | 26 July 2016 Paper

Paper

Characterizing and mitigating vibrations for SCExAO

Julien Lozi, Olivier Guyon, Nemanja Jovanovic, Garima Singh, Sean Goebel, Barnaby Norris, Hirofumi Okita

Proceedings Volume 9909, 99090J (2016) https://doi.org/10.1117/12.2233040

KEYWORDS: Telescopes, Computer programming, Telescopes, Adaptive optics, Wavefront sensors, Wavefronts, Cameras, Computer programming, Point spread functions, Coronagraphy, Data modeling, Turbulence

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Proceedings Article | 24 July 2014 Paper

Paper

High-z gamma-ray bursts for unraveling the dark ages mission HiZ-GUNDAM

Daisuke Yonetoku, Tatehiro Mihara, Tatsuya Sawano, Hirokazu Ikeda, Atsushi Harayama, Shunsuke Takata, Kazuki Yoshida, Hiroki Seta, Asuka Toyanago, Yasuaki Kagawa, Kentaro Kawai, Nobuyuki Kawai, Takanori Sakamoto, Motoko Serino, Shunsuke Kurosawa, Shuichi Gunji, Toru Tanimori, Toshio Murakami, Yoichi Yatsu, Kazutaka Yamaoka, Atsumasa Yoshida, Koji Kawabata, Toshio Matsumoto, Koji Tsumura, Shuji Matsuura, Mai Shirahata, Hirofumi Okita, Kensi Yanagisawa, Michitoshi Yoshida, Kentaro Motohara

Proceedings Volume 9144, 91442S (2014) https://doi.org/10.1117/12.2055041

KEYWORDS: Sensors, Near infrared, X-ray imaging, X-rays, Image sensors, Capacitance, Telescopes, Satellites, Gamma radiation, Analog electronics

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Proceedings Article | 6 August 2010 Paper

Paper

Antarctic Infra-Red Telescope with a 40cm primary mirror (AIRT40): development and improvement

Hirofumi Okita, Takashi Ichikawa, Tomohiro Yoshikawa, Ramsey Lundock, Kentaro Kurita

Proceedings Volume 7733, 77331U (2010) https://doi.org/10.1117/12.856576

KEYWORDS: Telescopes, Mirrors, Astronomy, Current controlled current source, Atmospheric turbulence, Spatial resolution, Domes, Optical tracking, Venus

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Proceedings Article | 10 July 2008 Paper

Paper

A 40-cm infrared telescope in Antarctica

Chihiro Murata, Takashi Ichikawa, Ramsey Guy Lundock, Yuichiro Taniguchi, Hirohumi Okita

Proceedings Volume 7012, 701229 (2008) https://doi.org/10.1117/12.787527

KEYWORDS: Telescopes, Space telescopes, Astronomy, Domes, Mirrors, Wind energy, Aluminum, Cameras, Control systems, Sensors

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Showing 5 of 29 publications

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