An ellipsoidal modulation in X-ray Nova VELA 1993 (=GRS 1009-45)
Abstract
We present the first optical observations of the soft X-ray transient Nova Vela 1993, taken during quiescence in 1995 and 1996. From the R-band photometry with a mean magnitude of 20.6, we find an orbital, ellipsoidal modulation with an amplitude of 0.23 mag at a period of 6.86+/-0.12 h. The optical spectra show only broad double-peaked Hα emission presumably arising from the accretion disc. We estimate the spectral type for the secondary to be late-G/early-K, which is consistent with the value for the mean density of the Roche lobe filling secondary star, obtained using the orbital period. By modelling the optical ellipsoidal modulations of the secondary star we determine a firm 95 per cent lower limit to the binary inclination of 37 deg.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- October 1996
- DOI:
- 10.1093/mnras/282.4.L47
- Bibcode:
- 1996MNRAS.282L..47S
- Keywords:
-
- ACCRETION;
- ACCRETION DISCS;
- BINARIES: CLOSE;
- STARS: INDIVIDUAL: NOVA VELA 1993;
- STARS: VARIABLES: OTHER;
- X-RAYS: STARS