LUT reveals a new mass-transferring semi-detached binary

Journal Article · Tue Dec 01 04:00:00 EST 2015 · The Astronomical Journal (Online)

DOI:https://doi.org/10.1088/0004-6256/150/6/193· OSTI ID:22890171

Qian, S. -B.; Zhou, X.; Zhu, L. -Y.; Zhao, E. -G.; Zhang, J.; Zhang, B.; Liao, W. -P. ^[1]; Zejda, M. ^[2]

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1. Yunnan Observatories, Chinese Academy of Sciences (CAS), P.O. Box 110, 650011 Kunming (China)
2. Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlářská 2, CZ-611 37 Brno (Czech Republic)

GQ Dra is a short-period eclipsing binary in a double stellar system that was discovered by Hipparcos. Complete light curves in the UV band were obtained with the Lunar-based Ultraviolet Telescope in 2014 November and December. Photometric solutions are determined using the W–D (Wilson and Devinney) method. It is discovered that GQ Dra is a classical Algol-type semi-detached binary where the secondary component is filling the critical Roche lobe. An analysis of all available times of minimum light suggests that the orbital period is increasing continuously at a rate of P-dot =+3.48(±0.23)×10{sup −7} days yr{sup −1}. This could be explained by mass transfer from the secondary to the primary, which is in agreement with the semi-detached configuration with a lobe-filling secondary. By assuming a conservation of mass and angular momentum, the mass transfer rate is estimated as m-dot =9.57(±0.63)×10{sup −8} M{sub ⊙} yr{sup −1}. All of these results reveal that GQ Dra is a mass-transferring semi-detached binary in a double system that was formed from an initially detached binary star. After the massive primary evolves to fill the critical Roche lobe, the mass transfer will be reversed and the binary will evolve into a contact configuration with two sub-giant or giant component stars.

• OSTI ID: 22890171
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 6 Vol. 150; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ANGULAR MOMENTUM
BINARY STARS
CONFIGURATION
ECLIPSE
MASS TRANSFER
ROCHE EQUIPOTENTIALS
STAR EVOLUTION
TELESCOPES
ULTRAVIOLET RADIATION