Abstract
AA Dor is an eclipsing, close, post common-envelope binary (PCEB) consisting of a sdOB primary star and an unseen secondary with an extraordinary small mass (M 2≈ 0.066 M ⊙)—formally a brown dwarf. The brown dwarf may have been a former planet which survived a common envelope (CE) phase and has even gained mass.
A recent determination of the components’ masses from results of NLTE spectral analysis and subsequent comparison to evolutionary tracks shows a discrepancy compared to masses derived from radial-velocity and the eclipse curves. Phase-resolved high-resolution and high-SN spectroscopy was carried out in order to investigate this problem.
We present results of a NLTE spectral analysis of the primary, an analysis of its orbital parameters, and discuss possible evolutionary scenarios.
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Rauch, T. AA Dor—An Eclipsing sdOB—Brown Dwarf Binary. Astrophys Space Sci 291, 275–282 (2004). https://doi.org/10.1023/B:ASTR.0000044333.13490.66
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DOI: https://doi.org/10.1023/B:ASTR.0000044333.13490.66