The optical counterpart of the X-ray binary in the globular cluster NGC 6712.
Abstract
Results are presented on R and B high-resolution imaging of the field of the X-ray source in the globular cluster NGC 6712, carried out with the Sub-Pupil Imager and the Photon-Counting Detector CP40. The images reveal the presence of two new stars of 21st magnitude in the B band, namely S and Z, which are 0.3 arcsec apart and are located within less than 0.25 arcsec of the U bright object in the field. The B images also show that the Z star is highly variable, by more than 1 mag. It is suggested that star Z is a strong candidate for being the optical counterpart of the X-ray/radio source and, thus, should be also the U object.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1990
- Bibcode:
- 1990A&A...239..155N
- Keywords:
-
- Globular Clusters;
- Variable Stars;
- X Ray Binaries;
- Astronomical Photometry;
- Color-Magnitude Diagram;
- Radio Sources (Astronomy);
- Stellar Spectra;
- Astronomy