Spectroscopic analysis of nearby lower-main-sequence stars |
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Authors: | X M Wang J R Shi G Zhao |
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Institution: | Department of Astronomy, Beijing Normal University, Beijing 100875, China;National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China |
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Abstract: | Abundances of O, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba are determined for 30 nearby lower-main-sequence stars in the Northern sky using high-resolution, high signal-to-noise ratio spectra. Our results show an equilibrium of Fe/H]I and Fe/H]II and a much smaller star-to-star scatter of the abundance ratios as a function of metallicity compared with the results of Kotoneva et al. The non-local thermodynamic equilibrium (non-LTE) corrections for oxygen are considered and found to be small (~?0.04 dex) . A flat trend of O/Fe] exists over the whole metallicity range. The non-LTE effects for some important elements are discussed, and it is found that the abundance pattern for our programme stars is very similar to that of F and G dwarfs. |
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Keywords: | line: formation stars: abundances stars: late-type Galaxy: evolution |
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