发表机构
Kwansei Gakuin University; Tohoku University; Waseda Institute for Advanced Study (WIAS), Waseda University; Center for Data Science, Waseda University; National Astronomical Observatory of Japan; The Graduate University for Advanced Studies（关西学院大学; 东北大学; 早稻田大学先进理工学研究科; 早稻田大学数据科学中心; 日本国立天文台; 综合研究大学院大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文介绍PEGASUS巡天，利用昴星团望远镜PFS光谱数据，基于发射线星系三维分布探测z>1处的大尺度结构，识别星系群、丝状结构和空洞，为研究环境对星系演化的影响提供基础。
AI 中文摘要
为了全面理解环境对星系演化的影响，精确绘制星系（包括低质量构建块）的分布并深入检验其性质至关重要。利用昴星团望远镜上的超主焦点相机（Hyper Suprime-Cam, HSC）进行的深窄带成像观测，系统性地探测了$0.4\leq z\leq1.6$范围内作为H$\alpha$、[O {\footnotesize II}]和[O {\footnotesize III}]发射线星系的低质量恒星形成星系的分布。我们利用昴星团望远镜上的`Ōnohi`ula - 主焦点摄谱仪（Prime Focus Spectrograph, PFS），对以COSMOS场为中心约1.8平方度区域内、基于窄带的发射线通量$\geq 2\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$的发射线星系进行了全面的光谱后续观测。本文概述了数据产品，并展示了$z>1$处的大尺度结构。9917个目标中观测了9079个，成功确认了92%观测目标的红移。我们基于每个红移处520-920个恒星质量$M_\star\geq10^{9.5}~M_{\odot}$的[O {\footnotesize II}]发射线星系的三维分布，调查了$z=1.19$、$1.47$和$1.60$处的星系群、丝状大尺度结构和空洞。具有晕质量$1\times10^{12}-6\times10^{13}~M_{\odot}$的星系群沿丝状结构被识别，而质量最大的星系群位于丝状结构最密集的交点处，这与宇宙学模拟的预测一致。隐藏在表面密度图中的空洞在体积密度图中被稳健地提取出来。我们的光谱样本为在后续论文中量化星系沿不同环境向宇宙正午时期演化提供了强大的基础。
英文摘要
To comprehensively understand the environmental effects on galaxy evolution, it is crucial to precisely map the distribution and thoroughly examine the properties of galaxies, including low-mass building blocks. Deep narrow-band imaging observations conducted with Hyper Suprime-Cam (HSC) on the Subaru Telescope systematically probed the distribution of low-mass star-forming galaxies as H$α$, [O {\footnotesize II}], and [O {\footnotesize III}] emission-line galaxies at $0.4\leq z\leq1.6$. We perform a comprehensive spectroscopic follow-up observation of these emission-line galaxies with narrow-band-based emission-line fluxes $\geq 2\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$ within $\approx1.8$ deg$^2$ area centered on the COSMOS field using `Ōnohi`ula - Prime Focus Spectrograph (PFS) on the Subaru Telescope. In this paper, we outline the data product and present the large-scale structures at $z>1$. 9079 out of 9917 of the targets are observed, and the redshifts of 92\%~of the observed targets are successfully confirmed. We survey groups, filamentary large-scale structures, and voids at $z=1.19$, $1.47$, and $1.60$ based on the three-dimensional distribution of $520-920$ [O {\footnotesize II}] emission-line galaxies with stellar masses $M_\star\geq10^{9.5}~M_{\odot}$ at each redshift. Groups with halo masses $1\times10^{12}-6\times10^{13}~M_{\odot}$ are identified along the filaments, whereas the most massive groups are located at the densest intersections of filaments as predicted by cosmological simulations. Voids hidden on the surface density maps are robustly extracted on the volume density map. Our spectroscopic sample provides a powerful basis for quantifying the evolution of galaxies along the diverse environments back in time toward cosmic noon epoch in forthcoming papers.
Comments21 pages, 16 figures, submitted to PASJ
