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arXiv · 0806.2709

Improved parameters of the hydrogen-deficient binary star KSPer

Tonu Kipper·Valentina Klochkova
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Abstract

Using the high resolution spectral observations obtained with the Nasmyth Echelle Spectrograph NES of the 6m telescope we analysed the optical spectrum of the hydrogen-deficient binary star KSPer. The atmospheric parameters derived are: effective temperature Teff=9500+/-300 K, surface gravity log g=2.0+/-0.5, and microturbulent velocity Vt=9.5+/-0.5km/s. The hydrogen deficiency is H/He=3x10^{-5}, iron abundance is reduced by 0.8dex; nitrogen abundance is very high [N/Fe]=1.4, but carbon and oxygen abundances are low. The star luminosity is log L/Lo=3.3. A complex absorption and emission structure of the NaI D doublet was revealed. We suggest that the emission component forms in the circumbinary gaseous envelope.

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Tonu Kipper, Valentina Klochkova. 2008-06-17. Improved parameters of the hydrogen-deficient binary star KSPer. https://arxiv.org/abs/0806.2709

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