We present the results of a search for pulsations in six of the recently discovered carbon-atmosphere white dwarf ("hot DQ") stars. Based on our theoretical calculations, the star SDSS J142625.71+575218.3 is the only object expected to pulsate. We observe this star to be variable, with significant power at 417.7 s and 208.8 s (first harmonic), making it a strong candidate as the first member of a new class of pulsating white dwarf stars, the DQVs. Its folded pulse shape, however, is quite different from that of other white dwarf variables, and shows similarities with that of the cataclysmic variable AM CVn, raising the possibility that this star may be a carbon-transferring analog of AM CVn stars. In either case, these observations represent the discovery of a new and exciting class of object.
@article{arxiv.0803.2646,
title = {SDSS J142625.71+575218.3, a Prototype for a New Class of Variable White Dwarf},
author = {M. H. Montgomery and Kurtis A. Williams and D. E. Winget and Patrick Dufour and Steven Degennaro and James Liebert},
journal= {arXiv preprint arXiv:0803.2646},
year = {2009}
}
Comments
Accepted for publication in the ApJ Letters. 4 pages, 4 figures, Figure 4 reduced in resolution