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Title: WD1032 + 011, an inflated brown dwarf in an old eclipsing binary with a white dwarf
ABSTRACT We present the discovery of only the third brown dwarf known to eclipse a non-accreting white dwarf. Gaia parallax information and multicolour photometry confirm that the white dwarf is cool (9950 ± 150 K) and has a low mass (0.45 ± 0.05 M⊙), and spectra and light curves suggest the brown dwarf has a mass of 0.067 ± 0.006 M⊙ (70MJup) and a spectral type of L5 ± 1. The kinematics of the system show that the binary is likely to be a member of the thick disc and therefore at least 5-Gyr old. The high-cadence light curves show that the brown dwarf is inflated, making it the first brown dwarf in an eclipsing white dwarf-brown dwarf binary to be so.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
1707419
Publication Date:
NSF-PAR ID:
10292612
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
497
Issue:
3
Page Range or eLocation-ID:
3571 to 3580
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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