11 papers
Gas-Phase Metallicity and Nitrogen Abundances in Low-Mass Galaxies Down to at -- from JWST Lensing Cluster Surveys
Hiroya Umeda, Masami Ouchi, Kimihiko Nakajima +7
We analyze 405 deep JWST/NIRSpec spectra of star-forming galaxies at -- from DREAMS and other lensing-cluster surveys to study chemical enrichment in intrinsically fai…
The Mysterious Case of Iron in XMPs: Anomalous High log(Fe/O) Observed in Extremely Metal-Poor Galaxies HSCJ1631+4426 and SDSSJ0811+4730
Aaron Myszka, Themiya Nanayakkara, Karl Glazebrook +8
We present integral field spectroscopic observations of two local extremely metal-poor galaxies (XMPs), HSCJ1631+4426 and SDSSJ0811+4730, obtained with the Keck Cosmic Web Imager (…
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…
A UV-Luminous Galaxy at z=11 with Surprisingly Weak Star Formation Activity
Yuichi Harikane, Pablo G. Perez-Gonzalez, Javier Alvarez-Marquez +8
One of the major discoveries by the James Webb Space Telescope (JWST) is the identification of a large population of luminous galaxies at , challenging theoretical models for…
Near-infrared Variability Detected in the Young Star-Forming Dwarf Galaxy SBS 0335-052E
Shun Hatano, Mitsuru Kokubo, Masami Ouchi +17
SBS~0335-052E is a young star-forming dwarf galaxy with a total stellar mass of and an extremely low metallicity (), which…
Fe Abundances of Early Galaxies at Derived with Deep JWST Spectra
Minami Nakane, Masami Ouchi, Kimihiko Nakajima +12
We derive Fe-abundance ratios of 7 galaxies at with whose JWST/NIRSpec spectra achieve very high signal-to-noise ratios, , a…