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arXiv · 2101.05463

Hyper Suprime-Cam Legacy Archive

Masayuki Tanaka·Hiroyuki Ikeda·Kazumi Murata·Satoshi Takita·Sogo Mineo·Michitaro Koike·Yuki Okura·Sumiko Harasawa
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Abstract

We present the launch of the Hyper Suprime-Cam Legacy Archive (HSCLA), a public archive of processed, science-ready data from Hyper Suprime-Cam (HSC). HSC is an optical wide-field imager installed at the prime focus of the Subaru Telescope and has been in operation since 2014. While ~1/3 of the total observing time of HSC has been used for the Subaru Strategic Program (SSP), the remainder of the time is used for PI programs. We have processed the data from these PI programs and make the processed, high quality data available to the community through HSCLA. The current version of HSCLA includes data taken in the first year of science operation, 2014. We provide both individual and coadd images as well as photometric catalogs. The photometric catalog from the coadd is loaded to the database, which offers a fast access to the large catalog. There are other online tools such as image browser and image cutout tool and they will be useful for science analyses. The coadd images reach 24-27th magnitudes at $5σ$ for point sources and cover approximately 580 square degrees in at least one filter with 150 million objects in total. We perform extensive quality assurance tests and verify the photometric and astrometric quality of the data to be good enough for most scientific explorations. However, the data are not without problems and users are referred to the list of known issues before exploiting the data for science. All the data and documentations can be found at the data release site, https://hscla.mtk.nao.ac.jp/.

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Masayuki Tanaka, Hiroyuki Ikeda, Kazumi Murata, Satoshi Takita, Sogo Mineo, Michitaro Koike, Yuki Okura, Sumiko Harasawa. 2021-01-14. Hyper Suprime-Cam Legacy Archive. https://doi.org/10.1093/pasj%2Fpsab034

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