Publication details

Apsidal motion in southern eccentric eclipsing binaries: GL Car, QX Car, NO Pup and V366 Pup



Year of publication 2008
Type Article in Periodical
Magazine / Source Monthly Notices of the Royal Astronomical Society
MU Faculty or unit

Faculty of Science

Field Astronomy and astrophysics
Keywords binaries: eclipsing; stars: fundamental parameters ; stars: individual: GL Car ; QX Car; NO Pup; V366 Pup
Description The study of apsidal motion in eccentric eclipsing binaries (EEB) provides an important observational test of theoretical models of stellar structure and evolution. The Southern hemisphere contains many interesting and also neglected binary systems. New accurate photoelectric times of minimum light have been obtained for the detached early-type Southern hemisphere EEB GL Car (P = 2.42d,e = 0.15), QX Car (4.48d, 0.15), NO Pup (1.26d, 0.13) and V366 Pup (2.48d, 0.47). The O-C diagrams are analysed using all reliable timings found in the literature and improved or new values for the elements of the apsidal motion are computed. We find more precise, relatively short periods of apsidal motion of about 25.2, 362, 38.3 and 285yr and corresponding internal structure constants, log k2, -1.88, -2.08, -2.32 and -2.38 for GL Car, QX Car, NO Pup and V366 Pup, respectively, with the assumption that the component stars rotate pseudo-synchronously. The relativistic effects are small, being about 3-12 per cent of the total apsidal motion rate in all systems. Based on observations made at the South Africa Astronomical Observatory, Sutherland, South Africa and Mt John University Observatory, University of Canterbury, Lake Tekapo, New Zealand.
Related projects: