Observations of Cygnus X-1 on board the space station Salyut 4.
Abstract
Results are presented for observations of Cyg X-1 in the energy range from 0.2 to 10 keV with the Filin X-ray spectrometer aboard the Salyut 4 space station. A substantial change in X-ray flux and source spectral characteristics was observed on one day, and this is identified with a transition from a 'dip' to some mean level of the low state of source activity. On another day, the flux had a low mean value, but about 20 powerful X-ray bursts with an average duration of no more than 1 sec were detected for 5 min in the energy range from 2 to 10 keV. These results are evaluated in terms of the source model involving an accreting black hole in a binary system.
- Publication:
-
Pisma v Astronomicheskii Zhurnal
- Pub Date:
- February 1977
- Bibcode:
- 1977PAZh....3...63S
- Keywords:
-
- Binary Stars;
- Black Holes (Astronomy);
- Spaceborne Astronomy;
- X Ray Sources;
- Astronomical Spectroscopy;
- Salyut Space Station;
- Spectrum Analysis;
- X Ray Astronomy;
- Astronomy;
- Black Holes:X-Ray Sources;
- Spectra:X-Ray Sources