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arXiv · 0712.1542

Duplicity and Evolution Status of the Early-Type Be Star V622 Per, the Member of the ChiPer Open Star Cluster

S. L. Malchenko
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Abstract

Radial velocities analysis based on high-resolution spectra, obtained in the H$α$ region and low resolution spectra obtained in the region 4420-4960Åtogether with radial velocities, taken from other published sources allow us to calculate orbital parameters of the massive binary system V622 Per. It is shown that the system has an orbital period 5.214(29) days, T$_0$ = 2450661(4) and is a post mass transfer binary. From light curve analysis of the ellipsoidal variability we obtained inclination angle of the system and temperature of the components. Luminosity ration of the components was found of about 4:1. T$_{eff}$ and $log g$ were estimated for each component. It is shown that primary, less massive but more bright star, is an evolved object that has lost large part of its mass during the evolution. Estimations of chemical composition of the primary show noticeable enrichment by products of the CNO cycles. E.g. He/H reaches 0.18, nitrogen is in excess of about 0.5 dex, carbon has low abundances (by 2-3 dex lower) and oxygen has 1 dex lower than solar abundance. The possible evolution of the binary with the known age 14 Myrs is discussed.

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S. L. Malchenko. 2007-12-10. Duplicity and Evolution Status of the Early-Type Be Star V622 Per, the Member of the ChiPer Open Star Cluster. https://arxiv.org/abs/0712.1542

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