activity
20222025
most citedEMPRESS. VIII. A New Determination of Primordial He Abundance with Extremely Metal-Poor Galaxies: A Suggestion of the Lepton Asymmetry and Implications for the Hubble Tension

104 citations · 127 across the 11 of their papers we have counts for

collaborators

11 papers

astro-ph.CO2025

Cosmic Himalayas in CROCODILE : Probing the Extreme Quasar Overdensities by Count-in-Cells analysis and Nearest Neighbor Distribution

Yuto Kuwayama, Yongming Liang, Kentaro Nagamine +7

The recently reported Cosmic Himalayas (CH) -- an extreme quasar overdensity at z~2 -- poses an apparent challenge to the Lambda CDM framework, with a reported significance of 16.9…

astro-ph.GA2025★ 3 cited

The AGORA High-resolution Galaxy Simulations Comparison Project. X: Formation and Evolution of Galaxies at the High-redshift Frontier

Hyeonyong Kim, Ji-hoon Kim, Minyong Jung +22

Recent observations from JWST have revealed unexpectedly luminous galaxies, exhibiting stellar masses and luminosities significantly higher than predicted by theoretical models at…

astro-ph.GA2025

Association of cold gas, massive galaxies, and AGNs in a filamentary protocluster traced by triple narrow-band imaging

Kazuki Daikuhara, Tadayuki Kodama, Haruka Kusakabe +13

We investigate galaxy populations in the HS1700+64 protocluster at , characterized by two prominent linear filaments traced by spatially extended Ly blobs. We conducted…

astro-ph.GA2025

EMPRESS. XV. A New Determination of the Primordial Helium Abundance Suggesting a Moderately Low Value

Hiroto Yanagisawa, Masami Ouchi, Akinori Matsumoto +18

We present a new constraint on the primordial helium abundance, , based on Subaru observations. A major source of uncertainty in previous determination…

astro-ph.CO2025

Probing the Cosmic Baryon Distribution and the Impact of Active Galactic Nuclei Feedback with Fast Radio Bursts in CROCODILE Simulation

Zhao Joseph Zhang, Kentaro Nagamine, Yuri Oku +6

We investigate the Missing Baryon problem using Fast Radio Bursts (FRBs) to trace cosmic baryons. Our CROCODILE simulations, performed with the GADGET3/4-OSAKA smoothed particle hy…

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…