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arXiv · 1610.00371

White Dwarf Mass Distribution

S. O. Kepler·Detlev Koester·Alejandra Daniela Romero·Gustavo Ourique·Ingrid Pelisoli
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Abstract

We present the mass distribution for all S/N > 15 pure DA white dwarfs detected in the Sloan Digital Sky Survey up to Data Release 12, fitted with Koester models for ML2/alpha=0.8, and with Teff > 10 000 K, and for DBs with S/N >10, fitted with ML2/alpha=1.25, for Teff > 16 000 K. These mass distributions are for log g > 6.5 stars, i.e., excluding the Extremely Low Mass white dwarfs. We also present the mass distributions corrected by volume with the 1/Vmax approach, for stars brighter than g=19. Both distributions have a maximum at M=0.624 Msun but very distinct shapes. From the estimated z-distances, we deduce a disk scale height of 300 pc. We also present 10 probable halo white dwarfs, from their galactic U, V, W velocities.

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S. O. Kepler, Detlev Koester, Alejandra Daniela Romero, Gustavo Ourique, Ingrid Pelisoli. 2016-10-02. White Dwarf Mass Distribution. https://arxiv.org/abs/1610.00371

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