Abstract

From SDSS DR7: Lessons on magnetic white dwarfs, composite spectra WD+dM, and progenitors of CVs

James Liebert (University of Arizona)

Lilia Ferrario and Dayal Wickramasinghe Australia Nationnal Unversity, Canberra

With the release of Kleinman et al's DR7 Catalog, an unprecedented number of white dwarfs (19,712) with SDSS spectra are available for study, with 521 magnetic DAH objects. However, this study may not have addressed all of the magnetic non-DAs, especially those with high fields and peculiar spectra. We reiterate: although the non-magnetic CVs have detached progenitors with short periods, we discuss whether magnetic CVs are paired with nondegenerate companions, as progenitors for polars and intermediate polars. If magnetic WDs can form from mergers of white dwarfs, this quandary may be partly explained. There is evidence that the mean WD mass increases with the magnetic field. that the mean mass of the WD increases with magnetic field strength.

Mode of presentation: oral