No one has ever seen a black hole. However, we strongly belive that such weird objects do exist. Cygnus X-1 is one of our primary candidates for a black hole. This object and several other galactic binary stars shows high-energy spectral characteristics very similar to that of AGNs. We are convinced that studying those "miniature AGNs" can turn out a significant contribution to the understanding of mysterious Active Galactic Nuclei.
The current job concerns the new, broad-band data from Ginga and GRO/OSSE satellites. The first one covers the X-rays from 2 keV to 30 keV, the latter one works in gamma-rays, in the range from 50 kev to 1000 keV. The simultaneous observations of Cygnus X-1 from both satellites provide us the unique coverage of the wide X-ray and gamma-ray spectrum. We are working on the analysis of the data and finding physical models consistent with the data. The work is made in collaboration with Andrzej A. Zdziarski from Nicolaus Copernicus Center in Warsaw.
13/01/1996