7 papers
ATLAS. III. Dust Around Little Red Dots: Hydrogen Line Ratios beyond Dust-free Non-Case B Models
Tomokazu Kiyota, Masami Ouchi, Hiroto Yanagisawa +7
We investigate broad hydrogen line ratios in little red dots (LRDs) using five high-redshift () sources from JWST/NIRSpec medium/high-resolution spectra in the DAWN JWST Archi…
ATLAS. II. Extremely High Incidence of Balmer Line Absorption with Predominant Blueshifts in LRDs: Statistical Insights through Comparison with Type 1 AGNs
Hiroto Yanagisawa, Masami Ouchi, Tomokazu Kiyota +6
We present the statistical properties of H and H line absorption in little red dots (LRDs) at --7.2 using archival JWST/NIRSpec spectra from the DAWN JWST Archi…
Chemical Abundance Ratios of Nitrogen Rich Galaxies Identified at : Observational Demographics and Models
Kuria Watanabe, Masami Ouchi, Kimihiko Nakajima +13
We present chemical abundance ratios of 8 nitrogen-rich ([N/O]) galaxies at identified by the first 4 years of the JWST observations, and compare these ratios wi…
A Scaling Relation of LRDs between Broad H and Bolometric Luminosities: Enhanced Broad H Emission Relative to Low- Type 1 AGN
Hiroto Yanagisawa, Masami Ouchi, Tomokazu Kiyota +6
We investigate the demography of little red dots (LRDs) using 37 objects at - with JWST/NIRSpec PRISM and grating spectra compiled from various JWST programs. We focus o…
DREAMS.II. Galaxy Demographics from Direct Te-Based Metallicities at z~2-10: Tracing the Evolution of the Mass-Metallicity and Fundamental Relations
Moka Nishigaki, Kimihiko Nakajima, Masami Ouchi +6
We present the statistics of line ratios and direct Te-based metallicities from JWST medium-resolution spectra of 292 galaxies at z=2-10, combining DREAMS observations with those o…
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…