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Title: An eclipsing 47 min double white dwarf binary at 400 pc
ABSTRACT We present the discovery of the eclipsing double white dwarf (WD) binary WDJ 022558.21−692025.38 that has an orbital period of 47.19 min. Following identification with the Transiting Exoplanet Survey Satellite, we obtained time series ground based spectroscopy and high-speed multiband ULTRACAM photometry which indicate a primary DA WD of mass $$0.40\pm 0.04\, \text{M}_\odot$$ and a $$0.28\pm 0.02\, \text{M}_\odot$$ mass secondary WD, which is likely of type DA as well. The system becomes the third-closest eclipsing double WD binary discovered with a distance of approximately 400 pc and will be a detectable source for upcoming gravitational wave detectors in the mHz frequency range. Its orbital decay will be measurable photometrically within 10 yr to a precision of better than 1 per cent. The fate of the binary is to merge in approximately 41 Myr, likely forming a single, more massive WD.  more » « less
Award ID(s):
1812874
PAR ID:
10503038
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; « less
Publisher / Repository:
Oxford Academic
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
525
Issue:
2
ISSN:
0035-8711
Page Range / eLocation ID:
1814 to 1823
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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