An Initial Survey of White Dwarfs in the Sloan Digital Sky Survey


Harris HC, Liebert J, Kleinman SJ, Nitta A, Anderson SF, Knapp GR, Krzesiński J, Schmidt G, Strauss MA, Vanden Berk D, et al. An Initial Survey of White Dwarfs in the Sloan Digital Sky Survey. The Astronomical Journal. 2003;126 :1023-1040.

Date Published:

August 1, 2003


An initial assessment is made of white dwarf and hot subdwarf starsobserved in the Sloan Digital Sky Survey. In a small area of sky (190square degrees), observed much like the full survey will be, 269 whitedwarfs (WDs) and 56 hot subdwarfs are identified spectroscopically whereonly 44 white dwarfs and five hot subdwarfs were known previously. Mostare ordinary DA (hydrogen atmosphere) and DB (helium) types. Inaddition, in the full survey to date, a number of WDs have been foundwith uncommon spectral types. Among these are blue DQ stars displayinglines of atomic carbon; red DQ stars showing molecular bands ofC2 with a wide variety of strengths; DZ stars where Ca andoccasionally Mg, Na, and/or Fe lines are detected; and magnetic WDs witha wide range of magnetic field strengths in DA, DB, DQ, and (probably)DZ spectral types. Photometry alone allows identification of starshotter than 12,000 K, and the density of these stars for 15-2 at Galactic latitudes of29°-62°. Spectra are obtained for roughly half of these hot