The broadband spectrum of 3C 120 observed by Bepposax

We study a broadband X-ray observation by BeppoSAX of the broad-line radio galaxy 3C 120. The primary X-ray continuum is well described by a power law with the photon index of Gamma similar to1.85 +/- 0.05 and a high-energy b reak or a cutoff. The obtained e-folding energy of similar to 100-300 keV c orresponds to kT similar to 50 keV in thermal-Compton models. A soft X-ray excess is found at a statistical significance of greater than or similar to 98%. Our physical best-fit model of the excess is optically thin emission from an extended plasma (with a luminosity of similar to2% of the total X-r ay luminosity), which interpretation is supported by an independent finding of an extended soft X-ray halo in 3C 120. We find a moderate Compton refle ction component together with a moderately broad Fe K alpha line with an eq uivalent width (similar to 10(2) eV) fully consistent with the strength of reflection, indicating their origin in an optically thick accretion disk ex tending relatively close to the central black hole. We observed strong spec tral variability during our 2 day observation with Gamma varying from simil ar to1.7 to similar to2 and correlated with the soft X-ray flux. The variab ility is very well modeled by thermal Comptonization in a hot plasma irradi ated by a variable UV flux. Both a hot patchy corona outflowing with a mild ly relativistic velocity away from a cold disk and a hot inner accretion fl ow overlapping with the cold disk are viable geometries. The presence of an outflow in the first case and an overlap between the hot and cold phases i n the second case are required by energy balance and the observed strength of Compton reflection.