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arXiv · 1905.12221

Second Data Release of the Hyper Suprime-Cam Subaru Strategic Program

Hiroaki Aihara·Yusra AlSayyad·Makoto Ando·Robert Armstrong·James Bosch·Eiichi Egami·Hisanori Furusawa·Junko Furusawa·Andy Goulding·Yuichi Harikane·Chiaki Hikage·Paul T. P. Ho·Bau-Ching Hsieh·Song Huang·Hiroyuki Ikeda·Masatoshi Imanishi·Kei Ito·Ikuru Iwata·Anton T. Jaelani·Ryota Kakuma·Kojiro Kawana·Satoshi Kikuta·Umi Kobayashi·Michitaro Koike·Yutaka Komiyama·Xiangchong Li·Yongming Liang·Yen-Ting Lin·Wentao Luo·Robert Lupton·Nate B. Lust·Lauren A. MacArthur·Yoshiki Matsuoka·Sogo Mineo·Hironao Miyatake·Satoshi Miyazaki·Surhud More·Ryoma Murata·Shigeru V. Namiki·Atsushi J. Nishizawa·Masamune Oguri·Nobuhiro Okabe·Sakurako Okamoto·Yuki Okura·Yoshiaki Ono·Masato Onodera·Masafusa Onoue·Ken Osato·Masami Ouchi·Takatoshi Shibuya·Michael A. Strauss·Naoshi Sugiyama·Yasushi Suto·Masahiro Takada·Yuhei Takagi·Tadafumi Takata·Satoshi Takita·Masayuki Tanaka·Tsuyoshi Terai·Yoshiki Toba·Hisakazu Uchiyama·Yousuke Utsumi·Shiang-Yu Wang·Wenting Wang·Yoshihiko Yamada
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Abstract

This paper presents the second data release of the Hyper Suprime-Cam Subaru Strategic Program, a wide-field optical imaging survey on the 8.2 meter Subaru Telescope. The release includes data from 174 nights of observation through January 2018. The Wide layer data cover about 300 deg^2 in all five broadband filters (grizy) to the nominal survey exposure (10min in gr and 20min in izy). Partially observed areas are also included in the release; about 1100 deg^2 is observed in at least one filter and one exposure. The median seeing in the i-band is 0.6 arcsec, demonstrating the superb image quality of the survey. The Deep (26 deg^2) and UltraDeep (4 deg^2) data are jointly processed and the UltraDeep-COSMOS field reaches an unprecedented depth of i~28 at 5 sigma for point sources. In addition to the broad-bands, narrow-band data are also available in the Deep and UltraDeep fields. This release includes a major update to the processing pipeline, including improved sky subtraction, PSF modeling, object detection, and artifact rejection. The overall data quality has been improved, but this release is not without problems; there is a persistent deblender problem as well as new issues with masks around bright stars. The user is encouraged to review the issue list before utilizing the data for scientific explorations. All the image products as well as catalog products are available for download. The catalogs are also loaded to a database, which provides an easy interface for users to retrieve data for objects of interest. In addition to these main data products, detailed galaxy shape measurements withheld from the Public Data Release 1 (PDR1) are now available to the community. The shape catalog is drawn from the S16A internal release, which has a larger area than PDR1 (160 deg^2). All products are available at the data release site, https://hsc-release.mtk.nao.ac.jp/.

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Hiroaki Aihara, Yusra AlSayyad, Makoto Ando, Robert Armstrong, James Bosch, Eiichi Egami, Hisanori Furusawa, Junko Furusawa, Andy Goulding, Yuichi Harikane, Chiaki Hikage, Paul T. P. Ho, Bau-Ching Hsieh, Song Huang, Hiroyuki Ikeda, Masatoshi Imanishi, Kei Ito, Ikuru Iwata, Anton T. Jaelani, Ryota Kakuma, Kojiro Kawana, Satoshi Kikuta, Umi Kobayashi, Michitaro Koike, Yutaka Komiyama, Xiangchong Li, Yongming Liang, Yen-Ting Lin, Wentao Luo, Robert Lupton, Nate B. Lust, Lauren A. MacArthur, Yoshiki Matsuoka, Sogo Mineo, Hironao Miyatake, Satoshi Miyazaki, Surhud More, Ryoma Murata, Shigeru V. Namiki, Atsushi J. Nishizawa, Masamune Oguri, Nobuhiro Okabe, Sakurako Okamoto, Yuki Okura, Yoshiaki Ono, Masato Onodera, Masafusa Onoue, Ken Osato, Masami Ouchi, Takatoshi Shibuya, Michael A. Strauss, Naoshi Sugiyama, Yasushi Suto, Masahiro Takada, Yuhei Takagi, Tadafumi Takata, Satoshi Takita, Masayuki Tanaka, Tsuyoshi Terai, Yoshiki Toba, Hisakazu Uchiyama, Yousuke Utsumi, Shiang-Yu Wang, Wenting Wang, Yoshihiko Yamada. 2019-08-22. Second Data Release of the Hyper Suprime-Cam Subaru Strategic Program. https://doi.org/10.1093/pasj%2Fpsz103

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