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Chemical composition of evolved stars of high galactic latitude

Sunetra Giridhar·A. Arellano Ferro
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Abstract

We have carried out abundance analysis for a sample of high galactic latitude supergiants in search of evolved stars. We find that HD 27381 has atmospheric parameters and an abundance pattern very similar to that of the post-AGB star HD 107369. HD 10285 and HD 25291 are moderately metal-poor and show the influence of mixing that has brought the products of NeNa cycle to the surface. The high galactic latitude B supergiant HD 137569 shows selective depletion of refractory elements normally seen in post-AGB stars. We find that the high velocity B type star HD 172324 shows moderate deficiency of Fe group elements but the CNO abundances are very similar to that of disk B supergiants. The observed variations in the radial velocities, transient appearance of emission components in hydrogen line profiles and doubling of O I lines at 7774Åsupport the possibility of this star being a pulsating variable or a binary star.

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Sunetra Giridhar, A. Arellano Ferro. 2005-09-02. Chemical composition of evolved stars of high galactic latitude. https://doi.org/10.1051/0004-6361%3A20041495

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