Photometric study of the over-contact binary star GSC 3822-1056

Abstract

Abstract.Here we present the first Johnson-Cousins VR C light curves of the over-contact binary star GSC 3822-1056. A period study and the light curve solution are also given. An extremely high rate of period increase (+11.6 s/century) was found. The origin of this period change can be: (i) partly covered light-time effect due to the orbital motion around the mass center of a possible third body; (ii) mass transfer between the components. The light curve was solved using the 1998 Wilson-Devinney Code. We examined the light curve with and without third light. Both solutions yielded a contact configuration with high temperature difference between the components. Despite the high degree of the contact ( f = 0.57), the temperature difference between the components ∆T = T primary − T secondary = 1045 K. The high mass ratio of the system and its other unusual properties suggest that GSC 3822-1056 may be a recently formed contact binary.

THE ANTICORRELATED NATURE OF THE PRIMARY AND SECONDARY ECLIPSE TIMING VARIATIONS FOR THEKEPLERCONTACT BINARIES

“…The greater sensitivity of the Qian (2001a) results is due to the long historical baseline of the plates they utilized (∼80 years vs. 4 years for the Kepler data base), in spite of the lower precision in timing the eclipses. We note, however, that larger detected values of Ṗorb in contact binaries are not unprecedented, e.g., LP UMa has P orb / Ṗorb ≃ 0.2 Myr (Csizmadia, Bíró, & Borkovits 2003).…”