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arXiv · 1503.03595

Kinematics and Velocity Ellipsoid of the Solar Neighborhood White Dwarfs

W. H. Elsanhoury·M. I. Nouh·H. I. Abdel-Rahman
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Abstract

To determine the velocity ellipsoid of the solar neighborhood white dwarfs, we use the space velocity components of stars. Two samples of white dwarfs are used, 20 pc and 25 pc samples. Beside the two main samples, the solar velocity and velocity dispersions are calculated for the four subsamples, namely DA, non - DA, hot and cool white dwarfs. Comparison between the results of 20 pc sample and those of 25 pc sample gives good agreement, while the comparison between the other subsamples gives bad agreement. Dependence of the velocity dispersions and solar velocity on the chemical composition and effective temperatures are discussed.

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W. H. Elsanhoury, M. I. Nouh, H. I. Abdel-Rahman. 2015-03-12. Kinematics and Velocity Ellipsoid of the Solar Neighborhood White Dwarfs. https://arxiv.org/abs/1503.03595

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