237 citations · 2.9k across the 92 of their papers we have counts for
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On the Abundance of Potassium in Metal-Poor Stars
Yoichi Takeda, Gang Zhao, Yu-Qin Chen +2
Based on extensive statistical-equilibrium calculations, we performed a non-LTE analysis of the K {\sc i} 7699 equivalent-width data of metal-deficient stars for the purpose of cla…
Photospheric Abundances of Volatile and Refractory Elements in Planet-Harboring Stars
Y. Takeda, B. Sato, E. Kambe +16
By using the high-dispersion spectra of 14 bright planet-harboring stars (along with 4 reference stars) observed with the new coude echelle spectrograph at Okayama Astrophysical Ob…
Oxygen Line Formation in Late-F through Early-K Disk/Halo Stars: Infrared O I Triplet and [O I] Lines
Yoichi Takeda
In order to investigate the formation of O {\sc i} 7771--5 and [O {\sc i}] 6300/6363 lines, extensive non-LTE calculations for neutral atomic oxygen were carried out for wide range…
Behavior of Sulfur Abundances in Metal-Poor Giants and Dwarfs
M. Takada-Hidai, Y. Takeda, S. Sato +6
LTE and NLTE abundances of sulfur in 6 metal-poor giants and 61 dwarfs (62 dwarfs, including the Sun) were explored in the range of -3 \lsim [Fe/H] \lsim using high-resoluti…