The Space Motions of DQ White Dwarfs

The web-based Villanova White Dwarf Catalog(http://www.astronomy.villanova.edu/WDCatalog/) currently contains 5,557 white dwarfs of which 93 DQ white dwarfs, (including 40 DQ stars discovered through the SDSS) were analyzed for T_eff, log g and C/Heby Dufour, Bergeron and Fontaine (2005, ApJ, 627, 404). We present the results of a kinematical analysis of the 93 DQ stars. For 53 DQ stars (not including the SDSS sample), the velocity dispersions σ (U), σ (V) and σ (W) and σ <T> are 67 km/s, 77 km/s, 49 km/s, and 85 km/s respectively while for a sample of 81 DA stars in the same range of M_v as the DQ stars, the respective velocity dispersions are 45, 31, 26, and 37 km/s respectively. Our results are discussed in the context of characterizing their evolutionary ancestors.

We acknowledge with gratitude the support of this work by NSF grant 05-07797.