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arXiv · 0810.2140

Two New Variable Hot DQ Stars

B. N. Barlow·B. H. Dunlap·R. Rosen·J. C. Clemens
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Abstract

We have discovered periodic variations in the light curves of two hot DQ stars from the Sloan Digital Sky Survey, SDSS J220029.08-074121.5 and SDSS J234843.30-094245.3. These are the second and third variables detected among the hot DQs and confirm the existence of a new class of variable white dwarf stars. The amplitudes of the variations are one half as large as those detected in the first discovered variable, SDSS J142625.71+575218.3, and required high signal-to-noise photometry to detect. The pulse shapes of the stars are not like those of known white dwarf pulsators but are similar to the first hot DQ variable, SDSS J142625.71+575218.3.

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B. N. Barlow, B. H. Dunlap, R. Rosen, J. C. Clemens. 2008-10-13. Two New Variable Hot DQ Stars. https://doi.org/10.1086/595584

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