Optical Counterpart of the X-ray Transient RX J0117·6-7330: Spectroscopy and Photometry
Abstract
We conducted spectroscopic and photometric observations of the optical companion of the X-ray transient RX J0117.6-7330 in the Small Magellanic Cloud, during a quiescent state. The primary star is identified as a B0.5 IIIe with a mass M * = (18 ± 2)M⨀ and bolometric magnitude M bol = -7.4 ± 0.2. The main spectral features are strong Hα emission, Hβ and Hγ emission cores with absorption wings, and narrow He I and O II absorption lines. Equivalent widths and full widths at half maximum of the main lines are listed. The average systemic velocity over our observing run is v r = (184 ± 4) km s-1; measurements over a longer period of time are needed to determine the binary period and the K velocity of the primary. We determine a projected rotational velocity v sin i = (145 ± 10) km s-1 for the Be star; if we assume a true rotational velocity at the equator v = (400 ± 50) km s-1, we deduce that the inclination angle of the system is i = (21 ± 3) deg.
- Publication:
-
Publications of the Astronomical Society of Australia
- Pub Date:
- August 1999
- DOI:
- 10.1071/AS99147
- arXiv:
- arXiv:astro-ph/9810028
- Bibcode:
- 1999PASA...16..147S
- Keywords:
-
- MAGELLANIC CLOUDS;
- X-RAY BINARIES;
- galaxies: Magellanic Clouds;
- stars: individual (RX J0117.6-7330);
- X-ray: binaries;
- Astrophysics
- E-Print:
- submitted to PASA