Four colour photometric observations of the X-ray binary HD 77581 (Vela X-1). II: Analysis of the light curve.
Abstract
Extended photometric observations of HD 77581, the optical counterpart of the X-ray source Vela X-1, in the Stromgren four-color system are discussed. These observations show changes in the light curve from one orbital period to another. A regular double-wave variation of the color index c1 (and possibly b-y) is observed. These observations are consistent with light and color variations predicted from a model of a tidally distorted rotating primary, using orbital parameters derived from spectroscopic observations.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- January 1977
- Bibcode:
- 1977A&A....54..167Z
- Keywords:
-
- Binary Stars;
- Light Curve;
- Stellar Spectrophotometry;
- Supergiant Stars;
- Ubv Spectra;
- X Ray Sources;
- Astronomical Spectroscopy;
- Color Photography;
- Luminous Intensity;
- Mass Ratios;
- Monochromatic Radiation;
- Astrophysics