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arXiv · 2108.13045

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

Abstract

The paper presents the third data release of Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP), a wide-field multi-band imaging survey with the Subaru 8.2m telescope. HSC-SSP has three survey layers (Wide, Deep, and UltraDeep) with different area coverages and depths, designed to address a wide array of astrophysical questions. This third release from HSC-SSP includes data from 278 nights of observing time and covers about 670 square degrees in all five broad-band filters at the full depth ($\sim26$~mag at $5\sigma$) in the Wide layer. If we include partially observed area, the release covers 1,470 square degrees. The Deep and UltraDeep layers have $\sim80\%$ of the originally planned integration times, and are considered done, as we have slightly changed the observing strategy in order to compensate for various time losses. There are a number of updates in the image processing pipeline. Of particular importance is the change in the sky subtraction algorithm; we subtract the sky on small scales before the detection and measurement stages, which has significantly reduced false detections. Thanks to this and other updates, the overall quality of the processed data has improved since the previous release. However, there are limitations in the data (for example, the pipeline is not optimized for crowded fields), and we encourage the user to check the quality assurance plots as well as a list of known issues before exploiting the data. The data release website is https://hsc-release.mtk.nao.ac.jp/.

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BibTeXRIS

Hiroaki Aihara, Yusra AlSayyad, Makoto Ando, Robert Armstrong, James Bosch, Eiichi Egami, Hisanori Furusawa, Junko Furusawa, Sumiko Harasawa, Yuichi Harikane, Bau-Ching Hsieh, Hiroyuki Ikeda, Kei Ito, Ikuru Iwata, Tadayuki Kodama, Michitaro Koike, Mitsuru Kokubo, Yutaka Komiyama, Xiangchong Li, Yongming Liang, Yen-Ting Lin, Robert H. Lupton, Nate B Lust, Lauren A. MacArthur, Ken Mawatari, Sogo Mineo, Hironao Miyatake, Satoshi Miyazaki, Surhud More, Takahiro Morishima, Hitoshi Murayama, Kimihiko Nakajima, Fumiaki Nakata, Atsushi J. Nishizawa, Masamune Oguri, Nobuhiro Okabe, Yuki Okura, Yoshiaki Ono, Ken Osato, Masami Ouchi, Yen-Chen Pan, Andrés A. Plazas Malagón, Paul A. Price, Sophie L Reed, Eli S. Rykoff, Takatoshi Shibuya, Mirko Simunovic, Michael A. Strauss, Kanako Sugimori, Yasushi Suto, Nao Suzuki, Masahiro Takada, Yuhei Takagi, Tadafumi Takata, Satoshi Takita, Masayuki Tanaka, Shenli Tang, Dan S. Taranu, Tsuyoshi Terai, Yoshiki Toba, Edwin L. Turner, Hisakazu Uchiyama, Bovornpratch Vijarnwannaluk, Christopher Z Waters, Yoshihiko Yamada, Naoaki Yamamoto, Takuji Yamashita. 2021-08-30. Third Data Release of the Hyper Suprime-Cam Subaru Strategic Program. https://doi.org/10.1093/pasj%2Fpsab122

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