Broad-band X-ray observations of the GRO J0422+32 X-ray nova by the "Mir-Kvant" observatory.

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 that 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 exponential cutoff is clearly seen in the spectrum in both cases. Such cutoffs are typical of thermal comptonization of low-frequency photons in the high-temperature plasma of accretion disks.