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arXiv · 2107.13141

The magnetic system SMSS J1606-1000 as a period bouncer

Adela Kawka·Stephane Vennes·Lilia Ferrario·M. S. Bessell·S. C. Keller·E. Paunzen·D. A. H. Buckley·D. Groenewald·J. Janik·M. Zejda
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Abstract

We report the discovery of a rare close binary system, SMSS J160639.78-100010.7, comprised of a magnetic white dwarf with a field of about 30 MG and a brown dwarf. We measured an orbital period of 92 min which is consistent with the photometric period. Minimum and maximum light occur at the orbital quadratures Phi=0.25 and 0.75, respectively, and cannot be caused by reflection on the brown dwarf, but, instead, by a spot on the synchronously rotating magnetic white dwarf. The brown dwarf does not fill its Roche lobe and the system may be in a low-accretion state or, more likely, in a detached state following episodes of mass transfer. SMSS J160639.78-100010.7 is the nearest known magnetic white dwarf plus brown dwarf system.

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Adela Kawka, Stephane Vennes, Lilia Ferrario, M. S. Bessell, S. C. Keller, E. Paunzen, D. A. H. Buckley, D. Groenewald, J. Janik, M. Zejda. 2021-07-28. The magnetic system SMSS J1606-1000 as a period bouncer. https://doi.org/10.1093/mnrasl%2Fslab085

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