Black-hole masses of type 1 AGN in the XMM-Newton bright serendipitous survey

Abstract

Aims. We derive masses of the central supermassive black hole (SMBH) and accretion rates for 154 type 1 AGN belonging to a well-defined X-ray-selected sample, the XMM-Newton serendipitous sample (XBS). Methods. We used the most recent "single-epoch" relations, based on Hβ and MgIIλ2798 Å emission lines, to derive the SMBH masses.We then used the bolometric luminosities, computed on the basis of an SED-fitting procedure, to calculate the accretion rates, both absolute and normalized to the Eddington luminosity (Eddington ratio). Results. The selected AGNs cover a range of masses from 107 to 1010 M with a peak around 8 × 108 M and a range of accretion rates from 0.01 to 50 M/year (assuming an efficiency of 0.1), with a peak at 1 M/year. The values of Eddington ratio range from 0.001 to 0.5 and peak at 0.1. © ESO 2013.