Elliposid-Ellipsoid Approximation for Close Binary Systems with Elliptical Orbits
Abstract
The shape of the components of close binaries with low-eccentricity elliptical orbits (nearly circular orbits) is investigated. These components are approximated by two ellipsoids whose semiaxes vary periodically in time, and the expressions for the ellipsoids include not only equilibrium (steady-state) but also dynamical (time varying) tidal distortions, of which the latter travel across the stellar surface near periastron. It is found that the dynamical tidal distortions cause the surface temperature of the star considered to vary periodically. Effects of changes in component shape and of temperature variations on a system's light curve are studied, and possible amplitudes of these effects are derived for the close binary system Y Cygni. The results indicate that variations in the light curve up to 0.01 mag may be expected.
- Publication:
-
Bulletin of the Astronomical Institutes of Czechoslovakia
- Pub Date:
- 1978
- Bibcode:
- 1978BAICz..29..361U
- Keywords:
-
- Binary Stars;
- Ellipsoids;
- Elliptical Orbits;
- Light Curve;
- Orbital Mechanics;
- Companion Stars;
- Orbital Elements;
- Stellar Temperature;
- Tides;
- Astronomy