BROAD-BAND X-RAY OBSERVATIONS OF THE GRO-J0422-RAY NOVA BY THE MIR-KVANT OBSERVATORY(32 X)

Observations of GRO J0422+32 X-Ray Nova with the instruments of the '' Mir-Kvant'' observatory show that the X-ray spectrum is similar to tha t of the well-known black-hole candidate Cyg X-1 in its ''low'' state. In the standard 2-20 keV X-ray range both have power law spectra with no strong soft component while at energies higher than 100 keV an exp onential cutoff is clearly seen in the spectrum in both cases. Such cu toffs are typical of thermal comptonization of low-frequency photons i n the high-temperature plasma of accretion disks.