Citation:
Date Published:
August 1, 2005Abstract:
Fifty-two magnetic white dwarfs have been identified in spectroscopicobservations from the Sloan Digital Sky Survey (SDSS) obtained betweenmid-2002 and the end of 2004, including Data Releases 2 and 3. Althoughnot as numerous or diverse as the discoveries from the first datarelease, the collection exhibits polar field strengths ranging from 1.5to ~1000 MG and includes two new unusual atomic DQA examples, amolecular DQ, and five stars that show hydrogen in fields above 500 MG.The highest field example, SDSS J2346+3853, may be the most stronglymagnetic white dwarf yet discovered. Analysis of the photometric dataindicates that the magnetic sample spans the same temperature range asfor nonmagnetic white dwarfs from the SDSS, and support is found forprevious claims that magnetic white dwarfs tend to have larger massesthan their nonmagnetic counterparts. A glaring exception to this trendis the apparently low-gravity object SDSS J0933+1022, which may have ahistory involving a close binary companion.A portion of the results presented here were obtained with the MMTObservatory, a facility operated jointly by the University of Arizonaand the Smithsonian Institution.