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arXiv · 1312.5088

The eclipsing post-common envelope binary CSS21055: a white dwarf with a probable brown-dwarf companion

K. Beuermann·S. Dreizler·F. V. Hessman·U. Backhaus·A. Boesch·T. -O. Husser·L. Nortmann·A. Schmelev·R. Springer
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Abstract

We report photometric observations of the eclipsing close binary CSS21055 (SDSS J141126+200911) that strongly suggest that the companion to the carbon-oxygen white dwarf is a brown dwarf with a mass between 0.030 and 0.074 Msun. The measured orbital period is 121.73min and the totality of the eclipse lasts 125s. If confirmed, CSS21055 would be the first detached eclipsing WD+BD binary. Spectroscopy in the eclipse could provide information about the companion's evolutionary state and atmospheric structure.

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K. Beuermann, S. Dreizler, F. V. Hessman, U. Backhaus, A. Boesch, T. -O. Husser, L. Nortmann, A. Schmelev, R. Springer. 2013-12-18. The eclipsing post-common envelope binary CSS21055: a white dwarf with a probable brown-dwarf companion. https://doi.org/10.1051/0004-6361%2F201322241

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