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The mysterious nature of HS2331+3905

S. Araujo-Betancor·B. T. Gaensicke·H. -J. Hagen·T. Marsh·J. Thorstensen·E. Harlaftis·R. E. Fried·D. Engels
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Abstract

We report the discovery of one unique cataclysmic variable drawn from the Hamburg Quasar Survey, HS2331+3905. Follow-up observations obtained over three years unveiled a very unusual picture. The large amplitude 3.5 h radial velocity variations obtained from our optical spectroscopy is not the orbital period of the system, as one would normally expect. Instead, extensive CCD photometry strongly suggests that HS2331+3905 is a short orbital period cataclysmic variable with Porb = 81.09 min, containing a cold white dwarf which appears to exhibit ZZ Ceti pulsations.

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S. Araujo-Betancor, B. T. Gaensicke, H. -J. Hagen, T. Marsh, J. Thorstensen, E. Harlaftis, R. E. Fried, D. Engels. 2004-02-11. The mysterious nature of HS2331+3905. https://arxiv.org/abs/astro-ph/0402270

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