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arXiv · 2305.08921

SILVERRUSH. XIII. A Catalog of 20,567 Ly$\alpha$ Emitters at $z=2-7$ Identified in the Full-depth Data of the Subaru/HSC-SSP and CHORUS Surveys

Satoshi Kikuta·Masami Ouchi·Takatoshi Shibuya·Yongming Liang·Hiroya Umeda·Akinori Matsumoto·Kazuhiro Shimasaku·Yuichi Harikane·Yoshiaki Ono·Akio K. Inoue·Satoshi Yamanaka·Haruka Kusakabe·Rieko Momose·Nobunari Kashikawa·Yuichi Matsuda·Chien-Hsiu Lee
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Abstract

We present 20,567 Ly$\alpha$ emitters (LAEs) at $z=2.2-7.3$ that are photometrically identified by the SILVERRUSH program in a large survey area up to 25 deg$^2$ with deep images of five broadband filters (grizy) and seven narrowband filters targeting Ly$\alpha$ lines at $z=2.2$, $3.3$, $4.9$, $5.7$, $6.6$, $7.0$, and $7.3$ taken by the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) and the Cosmic HydrOgen Reionization Unveiled with Subaru (CHORUS) survey. We select secure $>5\sigma$ sources showing narrowband color excesses via Ly$\alpha$ break screening, taking into account the spatial inhomogeneity of limiting magnitudes. After removing spurious sources by careful masking and visual inspection of coadded and multi-epoch images obtained over the 7 yr of the surveys, we construct LAE samples consisting of 6995, 4641, 726, 6124, 2058, 18, and 5 LAEs at $z=2.2$, 3.3, 4.9, 5.7, 6.6, 7.0, and 7.3, respectively, although the $z=7.3$ candidates are tentative. Our LAE catalogs contain 241 spectroscopically confirmed LAEs at the expected redshifts from previous work. We demonstrate that the number counts of our LAEs are consistent with previous studies with similar LAE selection criteria. The LAE catalogs will be made public on our project webpage with detailed descriptions of the content and ancillary information about the masks and limiting magnitudes.

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Satoshi Kikuta, Masami Ouchi, Takatoshi Shibuya, Yongming Liang, Hiroya Umeda, Akinori Matsumoto, Kazuhiro Shimasaku, Yuichi Harikane, Yoshiaki Ono, Akio K. Inoue, Satoshi Yamanaka, Haruka Kusakabe, Rieko Momose, Nobunari Kashikawa, Yuichi Matsuda, Chien-Hsiu Lee. 2023-05-15. SILVERRUSH. XIII. A Catalog of 20,567 Ly$\alpha$ Emitters at $z=2-7$ Identified in the Full-depth Data of the Subaru/HSC-SSP and CHORUS Surveys. https://arxiv.org/abs/2305.08921

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