Photometric and Spectroscopic Study of Ten Low Mass Ratio Contact Binary Systems: Orbital Stability, O'Connell Effect and Infrared Calcium Line Filling
Por:
Wadhwa, SS, Popowicz, A, Michel, R, Kostic, P, Vince, O, Tothill, NFH, De Horta, AY, Filipovic, MD
Publicada:
1 ago 2024
Resumen:
Low mass ratio contact binary systems are more likely to have unstable orbits and potentially merge. In addition, such systems exhibit characteristics such as starspots and high energy emissions (UV) suggestive of chromospheric and magnetic activity. Light curve modeling of ten contact binary systems is reported. All were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger candidates. Filling of the infrared calcium absorption lines is a marker of increased chromospheric activity. We use the available Large Sky Area Multi-Object Fiber Spectroscopic Telescope spectra along with matched standard spectra (broadened for rotation) to measure the excess filling of the central core depression flux of the two main infrared calcium absorption lines lambda 8542 and lambda 8662. We find that all reported contact binaries have excess filling of the core flux in the infrared calcium lines. Three of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact binaries. Analysis of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve modeling. Not an insignificant number of contact binary light curves exhibit the O'Connell effect, usually attributed to starspots. We discuss the inclusion of starspots in light curve solutions and how they influence the geometric and absolute parameters.
Filiaciones:
Wadhwa, SS:
Western Sydney Univ, Sch Sci, Locked Bag 1797, Penrith, NSW 1797, Australia
Popowicz, A:
Silesian Tech Univ, Dept Elect Elect Engn & Microelect, Akademicka 16, PL-44120 Gliwice, Poland
Michel, R:
UNAM, Inst Astron, AP 877, Ensenada 22800, BC, Mexico
Kostic, P:
Astron Observ, Volgina 7, Belgrade 11060, Serbia
Vince, O:
Astron Observ, Volgina 7, Belgrade 11060, Serbia
Tothill, NFH:
Western Sydney Univ, Sch Sci, Locked Bag 1797, Penrith, NSW 1797, Australia
De Horta, AY:
Western Sydney Univ, Sch Sci, Locked Bag 1797, Penrith, NSW 1797, Australia
Filipovic, MD:
Western Sydney Univ, Sch Sci, Locked Bag 1797, Penrith, NSW 1797, Australia
|