# Polaris B, an optical companion of the Polaris (α UMi) system: atmospheric parameters, chemical composition, distance and mass

@article{Usenko2008PolarisBA,
title={Polaris B, an optical companion of the Polaris ($\alpha$ UMi) system: atmospheric parameters, chemical composition, distance and mass},
author={Igor A. Usenko and Valentina Klochkova},
journal={Monthly Notices of the Royal Astronomical Society: Letters},
year={2008},
volume={387}
}
• Published 2 August 2007
• Physics
• Monthly Notices of the Royal Astronomical Society: Letters
We present an analysis of high-resolution spectroscopic observations of Polaris B, the optical companion of the Polaris Ab system. The star has a radial velocity of −16.6 to −18.9 km s −1 , and a projected rotational velocity v sin i = 110 km s −1 . The derived atmospheric parameters are: T eff = 6900 K; log g = 4.3; V t = 2.5 km s −1 . Polaris B has elemental abundances generally similar to those of the Cepheid Polaris A, although carbon, sodium and magnesium are close to the solar values. At…
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