SIMBAD references

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). We used the most recent ``single-epoch'' relations, based on Hβ and MgIIλ2798Å 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). The selected AGNs cover a range of masses from 10⁷ to 10¹⁰M_☉ with a peak around 8x10⁸M_☉ and a range of accretion rates from 0.01 to ∼50M_☉/year (assuming an efficiency of 0.1), with a peak at ∼1M_☉/year. The values of Eddington ratio range from 0.001 to ∼0.5 and peak at 0.1.