10 papers
Revealing α-Element's Past with Subaru/IRD: Oxygen Abundance of 35 Very Metal-Poor Stars from Near-IR OH lines
Bakuh Danang Setyo Budi, Wako Aoki, Nicholas Storm +10
Oxygen abundances in very and extremely metal-poor (V/EMP) stars provide critical constraints on early massive stars' nucleosynthesis. An Oxygen abundance analysis is presented for…
A Systematic NLTE Study of Very Metal-Poor Stars with Metallicity Down to dex. II. Lithium Abundance and New Insight to the Lithium Plateau
Hong-Liang Yan, Jinxiao Qin, Shuai Liu +12
Metal-poor stars are crucially important for understanding the early Galaxy, first stars, and the Universe. In this series of papers, we present a homogeneous non-local thermodynam…
SMSS J022423.27573705.1: An Extremely Metal-Poor Star with the Most Pronounced Weak -Process Signature
Hiroko Okada, Wako Aoki, Nozomu Tominaga +1
We present the measurement of 26 elemental abundances of SMSS J022423.27573705.1 (SMSS 02245737), an extremely metal-poor (EMP) star with a weak -process signature. We rep…
Potassium abundances in extremely metal poor stars: Implications for nucleosynthesis in the final stages of massive star evolution
M. N. Ishigaki, N. Tominaga, W. Aoki +5
We present a potassium (K) abundance analysis in extremely metal-poor (EMP) stars based on high-resolution () spectra obtained with the High Dispersion Spectrograph on…
Chemical abundances of seven stars in the GD-1 stream
Jing-Kun Zhao, Guang-Wei Li, Wako Aoki +13
We present the first detailed chemical abundances for seven GD-1 stream stars from Subaru/HDS spectroscopy. Atmospheric parameters were derived via color calibrations (…
Detailed Chemical Abundance Analysis of Metal-Poor Turn-Off Stars: One with [Fe/H] < -4 and Three with [Fe/H] < -3
Takuma Suda, Patrick Francois, Shinya Wanajo +3
We present the analysis of four new extremely metal poor turn-off stars thanks to high-resolution spectra obtained with the Subaru/HDS spectrograph. We determined the abundances an…