500 citations · 1.7k across the 32 of their papers we have counts for
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AGN number fraction in galaxy groups and clusters at z < 1.4 from the Subaru Hyper Suprime-Cam survey
Aoi Hashiguchi, Yoshiki Toba, Naomi Ota +20
One of the key questions on active galactic nuclei (AGN) in galaxy clusters is how AGN could affect the formation and evolution of member galaxies and galaxy clusters in the histor…
Optical IFU Observations of GOALS Sample with KOOLS-IFU on Seimei Telescope: Initial results of 9 U/LIRGs at 0.04
Yoshiki Toba, Satoshi Yamada, Kazuya Matsubayashi +23
We present ionized gas properties of 9 local ultra/luminous infrared galaxies (U/LIRGs) at 0.04 through IFU observations with KOOLS-IFU on Seimei Telescope. The observed targ…
What determines the HI gas content in galaxies?: morphological dependence of the HI gas fraction across M*-SFR plane
Shigeru V. Namiki, Yusei Koyama, Shuhei Koyama +5
We perform a stacking analysis of the HI spectra from the Arecibo Legacy Fast ALFA (ALFALFA) survey for optically-selected local galaxies from the Sloan Digital Sky Survey (SDSS) t…
A phase-space view of cold-gas properties of Virgo-cluster galaxies: multiple quenching processes at work?
Kana Morokuma-Matsui, Tadayuki Kodama, Tomoki Morokuma +5
We investigate the cold-gas properties of massive Virgo galaxies ( M) at ( is the radius where the mean interior density is 200 times the critic…
Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). IX. Identification of Two Red Quasars at z > 5.6
Nanako Kato, Yoshiki Matsuoka, Masafusa Onoue +14
We present the first discovery of dust-reddened quasars (red quasars) in the high-z universe (z >5.6). This is a result from the Subaru High-z Exploration of Low-Luminosity Quasars…
Subaru Hyper Suprime-Cam View of Quasar Host Galaxies at z < 1
Toru Ishino, Yoshiki Matsuoka, Shuhei Koyama +12
Active galactic nuclei (AGNs) are key for understanding the coevolution of galaxies and supermassive black holes (SMBHs). AGN activity is thought to affect the properties of their…
Do Galaxy Morphologies Really Affect the Efficiency of Star Formation during the Phase of Galaxy Transition?
Shuhei Koyama, Yusei Koyama, Takuji Yamashita +11
Recent simulations predict that the presence of stellar bulge suppress the efficiency of star formation in early-type galaxies, and this `morphological quenching' scenario is suppo…
Discovery of the First Low-Luminosity Quasar at z > 7
Yoshiki Matsuoka, Masafusa Onoue, Nobunari Kashikawa +45
We report the discovery of a quasar at z = 7.07, which was selected from the deep multi-band imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey.…
A universal correlation between star-formation activity and molecular gas properties across environments
Shuhei Koyama, Yusei Koyama, Takuji Yamashita +10
We present the molecular gas mass fraction () and star-formation efficiency (SFE) of local galaxies on the basis of our new CO() observations with the Nobeya…
The Quiescent Intracluster Medium in the Core of the Perseus Cluster
Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +213
Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host…