Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2010-08-11
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
Accepted for publication in MNRAS. 19 pages, including 15 figures and 6 tables. This version has been revised to include a mis
Scientific paper
With orbital periods of the order of tens of minutes or less, the AM Canum Venaticorum stars are ultracompact, hydrogen deficient binaries with the shortest periods of any binary subclass, and are expected to be among the strongest gravitational wave sources in the sky. To date, the only known eclipsing source of this type is the P = 28 min binary SDSS J0926+3624. We present multiband, high time resolution light curves of this system, collected with WHT/ULTRACAM in 2006 and 2009. We supplement these data with additional observations made with LT/RISE, XMM_Newton and the Catalina Real-Time Transient Survey. From light curve models we determine the mass ratio to be q = M2 / M1 = 0.041 +/- 0.002 and the inclination to be 82.6 +/- 0.3 deg. We calculate the mass of the primary white dwarf to be 0.85 +/- 0.04 solar masses and the donor to be 0.035 +/- 0.003 solar masses, implying a partially degenerate state for this component. We observe superhump variations that are characteristic of an elliptical, precessing accretion disc. Our determination of the superhump period excess is in agreement with the established relationship between this parameter and the mass ratio, and is the most precise calibration of this relationship at low q. We also observe a quasi-periodic oscillation in the 2006 data, and we examine the outbursting behaviour of the system over a 4.5 year period.
Copperwheat Chris M.
Dhillon Vik S.
Drake Andrew J.
Gaensicke Boris T.
Groot Paul J.
No associations
LandOfFree
SDSS J0926+3624: The shortest period eclipsing binary star does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with SDSS J0926+3624: The shortest period eclipsing binary star, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and SDSS J0926+3624: The shortest period eclipsing binary star will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-480096