103 citations · 241 across the 8 of their papers we have counts for
8 papers
Compositional differences between the component stars of eclipsing close binary systems showing chemical peculiarities
Yoichi Takeda, Inwoo Han, Dong-Il Kang +2
A spectroscopic study was carried out on the surface chemical abundances of CNO and several heavier elements in the primary and secondary components of 5 eclipsing close binaries a…
Photospheric carbon, nitrogen, and oxygen abundances of A-type main-sequence stars
Yoichi Takeda, Satoshi Kawanomoto, Naoko Ohishi +4
Based on the spectrum fitting method applied to CI 5380, NI 7486, and OI 6156-8 lines, we determined the abundances of C, N, and O for 100 mostly A-type main-sequence stars (late B…
Magnetic field and radial velocities of the star Chi Draconis A
Byeong-Cheol Lee, D. Gadelshin, Inwoo Han +13
We present high-resolution spectropolarimetric observations of the spectroscopic binary Chi Dra. Spectral lines in the spectrum of the main component Chi Dra A show variable Zeeman…
C, N, O, and Na Abundances of Cepheid Variables: Implications on the Mixing Process in the Envelope
Y. Takeda, D. -I. Kang, I. Han +2
With an aim of investigating the nature of evolution-induced mixing in the envelope of evolved intermediate-mass stars, we carried out an extensive spectroscopic study for 12 Cephe…
Lithium, Sodium, and Potassium Abundances in Sharp-Lined A-Type Stars
Yoichi Takeda, Dong-Il Kang, Inwoo Han +4
The abundances of alkali elements (Li, Na, and K) were determined from the Li I 6708, Na I 5682/5688, and K I 7699 lines by taking into account the non-LTE effect for 24 sharp-line…
Can Sodium Abundances of A-Type Stars Be Reliably Determined from Na I 5890/5896 Lines?
Yoichi Takeda, Dong-Il Kang, Inwoo Han +2
An extensive non-LTE abundance analysis based on Na I 5890/5896 doublet lines was carried out for a large unbiased sample of ~120 A-type main-sequence stars (including 23 Hyades st…