ASPCS
 
Back to Volume
Paper: Physical Parameters of DA White Dwarfs from the Sloan Digital Sky Survey
Volume: 372, 15th European Workshop on White Dwarfs
Page: 49
Authors: Ciechanowska, A.; Nalezyty, M.; Majczyna, A.; Madej, J.
Abstract: We present a new catalogue of masses, radii and bolometric luminosities for hot DA white dwarfs observed by the Sloan Digital Sky Survey (Data Release 4). Masses and radii of 7134 non-magnetic stars were determined from their observed effective temperatures Teff and surface gravities log g by the spectroscopic method. We have used here the grid of theoretical mass-radius relations for carbon-core stars with hydrogen-envelopes derived by Panei et al. (2000). Mass distribution of DA white dwarfs with Teff ≥ 12000 K has one maximum at M = 0.549M. However, we discovered the existence of the secondary maximum at about 0.393M for hotter white dwarf stars. We also turn attention to low-mass white dwarfs (M ≤ 0.45M) with helium-cores and list them explicitly. The star of the lowest mass in our catalogue is SDSS J204949.78+000547.3 with mass M = 0.162M and radius R = 16047 km.
Back to Volume