activity
20142026
most citedThe Hyper Suprime-Cam SSP Survey: Overview and Survey Design

1.1k citations · 8.7k across the 180 of their papers we have counts for

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Showing 2024Show all

16 papers · 1 filter

astro-ph.GA2024

EMPRESS. X. Spatially resolved mass-metallicity relation in extremely metal-poor galaxies: evidence of episodic star-formation fueled by a metal-poor gas infall

Kimihiko Nakajima, Masami Ouchi, Yuki Isobe +47

Using the Subaru/FOCAS IFU capability, we examine the spatially resolved relationships between gas-phase metallicity, stellar mass, and star-formation rate surface densities (Sigma…

astro-ph.GA2024

A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS). X. The Massive and Passive Nature of Radio Galaxies at

Yuta Yamamoto, Tohru Nagao, Takuji Yamashita +8

High- radio galaxies (HzRGs) are considered important objects for understanding the formation and evolution of massive galaxies in the early universe. However, till date, detail…

astro-ph.GA2024

SILVERRUSH. XIV. Lya Luminosity Functions and Angular Correlation Functions from ~20,000 Lya Emitters at z~2.2-7.3 from upto 24 HSC-SSP and CHORUS Surveys: Linking the Post-Reionization Epoch to the Heart of Reionization

Hiroya Umeda, Masami Ouchi, Satoshi Kikuta +11

We present the luminosity functions (LFs) and angular correlation functions (ACFs) derived from 18,960 Ly emitters (LAEs) at over a wide survey area of $\lesssim24 {…

astro-ph.GA2024★ 1 cited

A Galaxy with an Extremely Blue UV Slope at Identified by JWST Spectroscopy: Evidence for a Weak Nebular Continuum and Efficient Ionizing Photon Escape?

Hiroto Yanagisawa, Masami Ouchi, Kimihiko Nakajima +8

We investigate UV continuum slopes of 863 galaxies at using archival JWST/NIRSpec PRISM spectra obtained from major JWST GTO, ERS, and GO programs, including JADES, CE…

astro-ph.GA2024★ 10 cited

JWST/NIRSpec spectroscopy of intermediate-mass quiescent galaxies at

Riku A. Sato, Akio K. Inoue, Yuichi Harikane +9

We present the analysis of three intermediate-mass quiescent galaxies (QGs) with stellar masses of at redshifts using NIRSpec low-resolutio…

astro-ph.GA2024

The Physical Origin of Extreme Emission Line Galaxies at High redshifts: Strong {\sc [Oiii]} Emission Lines Produced by Obscured AGNs

Chenghao Zhu, Yuichi Harikane, Masami Ouchi +21

We present deep Subaru/FOCAS spectra for two extreme emission line galaxies (EELGs) at with strong {\sc[Oiii]}5007 emission lines, exhibiting equivalent widths (EWs) o…

astro-ph.GA2024

Low [O/Fe] Ratio in a Luminous Galaxy at the Early Cosmic Epoch (): Signature of Short Delay Time or Bright Hypernovae/Pair-Instability Supernovae?

Minami Nakane, Masami Ouchi, Kimihiko Nakajima +12

We present an [O/Fe] ratio of a luminous galaxy GN-z11 at derived with the deep public JWST/NIRSpec data. We fit the medium-resolution grating (G140M, G235M, and G395M) d…

astro-ph.GA2024★ 32 cited

Challenging the AGN scenario for JWST/NIRSpec LRD and non-LRD broad H emitters in light of non-detection of NIRCam photometric variability and X-ray

Mitsuru Kokubo, Yuichi Harikane

JWST has uncovered a substantial population of high- () galaxies exhibiting broad H emission line with a Full Width at Half Maximum exceeding 1,000 km/s. This po…

astro-ph.IM2024

FINER: Far-Infrared Nebular Emission Receiver for the Large Millimeter Telescope

Yoichi Tamura, Takeshi Sakai, Ryohei Kawabe +34

Unveiling the emergence and prevalence of massive/bright galaxies during the epoch of reionization and beyond, within the first 600 million years of the Universe, stands as a pivot…

astro-ph.GA2024★ 7 cited

JWST, ALMA, and Keck Spectroscopic Constraints on the UV Luminosity Functions at z~7-14: Clumpiness and Compactness of the Brightest Galaxies in the Early Universe

Yuichi Harikane, Akio K. Inoue, Richard S. Ellis +33

We present the number densities and physical properties of the bright galaxies spectroscopically confirmed at . Our sample is composed of 60 galaxies at $z_\mathrm{spec}…

astro-ph.GA2024★ 2 cited

Strong He I Emission Lines in High N/O Galaxies at Identified in JWST Spectra: High He/H Abundance Ratios or High Electron Densities?

Hiroto Yanagisawa, Masami Ouchi, Kuria Watanabe +14

We present HeI/H-flux and He/H-abundance ratios in three JWST galaxies with significant constraints on N/O-abundance ratios, GS-NDG-9422, RXCJ2248-ID, and GLASS150008 at $z\sim…

astro-ph.GA2024★ 1 cited

Dynamics of a Galaxy at z > 10 Explored by JWST Integral Field Spectroscopy: Hints of Rotating Disk Suggesting Weak Feedback

Yi Xu, Masami Ouchi, Hidenobu Yajima +9

We investigate the dynamics of GN-z11, a luminous galaxy at , carefully analyzing the public deep integral field spectroscopy (IFS) data taken with JWST NIRSpec IFU. While…

astro-ph.GA2024

Cosmic Himalayas: The Highest Quasar Density Peak Identified in a 10,000 deg Sky with Spatial Discrepancies between Galaxies, Quasars, and IGM HI

Yongming Liang, Masami Ouchi, Dongsheng Sun +27

We report the identification of a quasar overdensity in the BOSSJ0210 field, dubbed Cosmic Himalayas, consisting of 11 quasars at , the densest overdensity of quasars…

astro-ph.GA2024★ 3 cited

Balmer Decrement Anomalies in Galaxies at z ~ 6 Found by JWST Observations: Density-Bounded Nebulae or Excited H I Clouds?

Hiroto Yanagisawa, Masami Ouchi, Kimihiko Nakajima +11

We investigate the physical origins of the Balmer decrement anomalies in GS-NDG-9422 (Cameron et al. 2023) and RXCJ2248-ID (Topping et al. 2024) galaxies at whose $\mathr…

astro-ph.GA2024★ 12 cited

Tip of the iceberg: overmassive black holes at 4<z<7 found by JWST are not inconsistent with the local - relation

Junyao Li, John D. Silverman, Yue Shen +8

JWST is revealing a new remarkable population of high-redshift (), low-luminosity Active Galactic Nuclei (AGNs) in deep surveys and detecting the host galaxy stellar lig…

astro-ph.GA2024

Sub-Parsec-Scale Jet-Driven Water Maser with Possible Gravitational Acceleration in the Radio Galaxy NGC 1052

Seiji Kameno, Yuichi Harikane, Satoko Sawada-Satoh +5

We report sub-pc-scale observations of the 321-GHz HO emission line in the radio galaxy NGC 1052. The HO line emitter size is constrained in milliarcsec distributed…