BeppoSAX observation of Hercules A and MRC 0625-536

Abstract

We present BeppoSAX observations of the two FR I type radio galaxies Hercules A (3C 348) and MRC 0625-536 in the energy range $0.2 - 200$ keV. Data analysis shows that the X-ray flux from Hercules A is consistent with a diffuse thermal plasma emitting at $T \approx 4-5$ keV with a possible, but somewhat uncertain, contribution of a softer component at $T \approx 3 $ keV. The non thermal emission from the active nucleus must be significantly smaller than the thermal one, and no indication of relevant core obscuration by a surrounding torus was detected. The flux from MRC 0625-536 originates form an extended region and has been fitted to a thermal law with $T \approx 5.7$ keV and with a column density consistent with the galactic absorption. A spatially resolved spectral analysis does not show a relevant variation of the temperature and the metallicity across the diffuse emission zone. A non thermal spectral component, related to the nuclear activity, may be present in the innermost region with some possible amount of local obscuration, contributing $\lapp 10%$ to the total luminosity. Hard X-ray emission from MRC 0625-536 has been detected in the PDS (15 - 200 keV) that may be related either to its galactic core or to the intracluster region.