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Description
We presented the observed information of ten metal-poor halo stars with the metallicity range -2.3<[Fe/H]< -1.4 and derived their stellar parameters, acquired some elemental abundances relative to iron and discussed the relation between the abundance ratio and the metallicity. The stars were observed using the 6m telescope of the Special Astrophysical Observatory with the ECHELLE spectrometer PFES equipped with the CCD (1040x1160 pixels, pixel size 16x16{mu}m). The spectral wavelength coverage is of 430-798nm with the resolving power of 15000 and the signal-to-noise ratio is about 200. It was found that oxygen abundances are nearly constant at a level of 0.6dex for our metal-poor halo stars when the non-LTE correction is considered. The alpha-elements (Mg, Si, Ca and Ti) are overabundant relative to Fe and decrease with increasing metallicity. We also obtained a significant underabundant non-LTE [Na/Fe] ratio from NaI D lines which have large deviation from LTE assumption. Scandium is marginally overabundant with respect to iron and tends to decrease with increasing metallicity like the alpha-elements. Nearly solar value of [Cr/Fe] ratio and underabundant [Mn/Fe] ratio are obtained.
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