309 citations · 1k across the 14 of their papers we have counts for
14 papers
Absolute Magnitudes of Seismic Red Clumps in the Kepler Field and SAGA: the age dependency of the distance scale
Y. Q. Chen, L. Casagrande, G. Zhao +4
Red clump stars are fundamental distance indicators in astrophysics, although theoretical stellar models predict a dependence of absolute magnitudes with ages. This effect is parti…
Ages of 70 dwarfs of three populations in the solar neighborhood: considering O and C abundances in stellar models
Z. S. Ge, S. L. Bi, Y. Q. Chen +5
Oxygen and carbon are important elements in stellar populations. Their behavior refers to the formation history of the stellar populations. C and O abundances would also obviously…
Systematic non-LTE study of the [Fe/H] F and G dwarfs in the solar neighbourhood. II. Abundance patterns from Li to Eu
G. Zhao, L. Mashonkina, H. L. Yan +14
For the first time, we present an extensive study of stars with individual non-local thermodynamic equilibrium (NLTE) abundances for 17 chemical elements from Li to Eu in a sample…
Fundamental stellar parameters and age-metallicity relation of Kepler red giants in comparison with theoretical evolutionary tracks
Y. Takeda, A. Tajitsu, B. Sato +3
Spectroscopic parameters (effective temperature, metallicity, etc) were determined for a large sample of ~100 red giants in the Kepler field, for which mass, radius, and evolutiona…
Systematic NLTE study of the -2.6 < [Fe/H] < 0.2 F and G dwarfs in the solar neighbourhood. I. Stellar atmosphere parameters
T. Sitnova, G. Zhao, L. Mashonkina +9
We present atmospheric parameters for 51 nearby FG dwarfs uniformly distributed over the -2.60 < [Fe/H] < +0.20 metallicity range that is suitable for the Galactic chemical evoluti…
Carbon and oxygen abundances in stellar populations
P. E. Nissen, Y. Q. Chen, L. Carigi +2
Abundances of C, O, and Fe are determined for F and G main-sequence stars in the solar neighborhood in order to study trends and systematic differences in the C/Fe, O/Fe, and C/O r…
The CH(G) Index as a New Criterion for Selecting Red Giant Stars
Y. Q. Chen, G. Zhao, K. Carrell +2
We have measured the CH G band (CH(G)) index for evolved stars in the globular cluster M3 based on the Sloan Digital Sky Survey (SDSS) spectroscopic survey. It is found that there…
Deprojected analysis of Abell 1835 observed with Chandra and compared with XMM-Newton
Chengkui Li, Shumei Jia, Yong Chen +3
Using a deprojection technique, we study the X-ray properties of the galaxy cluster Abell 1835 observed with Chandra, including temperature, abundance, electron density, gas mass f…
The Kinematics and Chemistry of Red Horizontal Branch Stars in the Sagittarius Streams
W. B. Shi, Y. Q. Chen, K. Carrell +1
We have selelcted 556 Red Horizontal Branch (RHB) stars along the streams of the Sagittarius dwarf galaxy (Sgr) from SDSS DR7 spectroscopic data using a theoretical model. The meta…
Chemical composition of giants from two moving groups
F. Liu, Y. Q. Chen, G. Zhao +4
We present stellar parameters of 19 K-type giants and their abundances of 13 chemical elements (Al, Ba, Ca, Fe, K, Mg, Mn, Na, Ni, Sc, Si, Ti and V), selected from two moving group…
The Metallicity Gradient of the Thick Disk Based on Red Horizontal Branch Stars From SDSS DR8
Y. Q. Chen, G. Zhao, K. Carrell +1
Based on SDSS DR8, we have selected a sample of 1728 red horizontal branch stars with |Z|<3 kpc by using a color-metallicity relation and stellar parameters. The sample stars clear…
A Comparative Study on Lithium Abundances in Solar--Type Stars With and Without Planets
Y. Q. Chen, G. Zhao
We have investigated the abundance anomalies of lithium for stars with planets in the temperature range of 5600--5900 K reported by Israelian and coworkers, as compared to 20 norma…
Lithium abundances for 185 main-sequence stars - Galactic evolution and stellar depletion of lithium
Y. Q. Chen, P. E. Nissen, T. Benoni +1
We present a survey of lithium abundances in 185 main- sequence field stars with Teff between 5600 and 6600 K and [Fe/H] from -1.4 to +0.2 based on high-resolution spectra of 130 s…
Chemical composition of 90 F and G disk dwarfs
Y. Q. Chen, P. E. Nissen, G. Zhao +2
High resolution, high S/N spectra have been obtained for a sample of 90 F and G main-sequence disk stars covering the metallicity range -1.0 < [Fe/H] < +0.1, and have been analysed…