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arXiv · 1102.0505

Brown Dwarf Companions to White Dwarfs

M. R. Burleigh·P. R. Steele·P. D. Dobbie·J. Farihi·R. Napiwotzki·P. F. L. Maxted·M. A. Barstow·R. F. Jameson·S. L. Casewell·B. T. Gänsicke·T. R. Marsh
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Abstract

Brown dwarf companions to white dwarfs are rare, but recent infra-red surveys are slowly reveal- ing examples. We present new observations of the post-common envelope binary WD0137-349, which reveals the effects of irradiation on the ~ 0.05M* secondary, and new observations of GD 1400 which show that it too is a close, post-comon envelope system. We also present the lat- est results in a near-infrared photometric search for unresolved ultracool companions and to white dwarfs with UKIDSS. Twenty five DA white dwarfs were identified as having photometric excesses indicative of a low mass companion, with 8-10 of these having a predicted mass in the range asso- ciated with brown dwarfs. The results of this survey show that the unresolved (< 2") brown dwarf companion fraction to DA white dwarfs is 0.3 \leq fWD+BD \leq 1.3%.

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M. R. Burleigh, P. R. Steele, P. D. Dobbie, J. Farihi, R. Napiwotzki, P. F. L. Maxted, M. A. Barstow, R. F. Jameson, S. L. Casewell, B. T. Gänsicke, T. R. Marsh. 2011-02-02. Brown Dwarf Companions to White Dwarfs. https://doi.org/10.1063/1.3570983

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