We determined masses for the 7167 DA and 507 DB white dwarf stars classified as single and non-magnetic in Data Release 4 of the Sloan Digital Sky Survey (SDSS). We obtained revised Teff and logg determinations for the most massive stars by fitting the SDSS optical spectra with a synthetic spectra grid derived from model atmospheres extending to logg = 10.0. We also calculate radii from evolutionary models and create volume-corrected mass distributions for our DA and DB samples. The mean mass for the DA stars brighter than g = 19 and hotter than Teff = 12000K is . For the 150 DBs brighter than g = 19 and hotter than Teff = 16000K, we find . It appears the mean mass for DB white dwarf stars may be significantly larger than that for DAs. We also report the highest mass white dwarf stars ever found, up to .
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 2007
- white dwarfs;
- Accepted for publication in the MNRAS, 27 pages, 14 figures and 6 tables. Corrected sky coverage area and densities