Optical properties of HZ Herculis.
Abstract
The optical properties of HZ Her are analyzed, and several parameters of the Her X-1-HZ Her binary system are estimated. The phase agreement of the X-ray and optical variations, the dependence of the average optical luminosity upon the 35-day X-ray cycle, and the energy budget of the optical variations are studied, using recent observational data. The period, amplitude, and phase of the small-scale optical light variations found by Jones et al. during times of extended optical inactivity are also investigated. The light curve and the radial-velocity variations of HZ Her are analyzed, using several simple models for the brightness distribution across the face of the star. The masses of Her X-1 and HZ Her are estimated by four different methods. Subject headings: binaries - stars, individual - X-ray sources
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1974
- DOI:
- 10.1086/152957
- Bibcode:
- 1974ApJ...191..211B