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

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.

Based on observations collected at the Telescopio Nazionale Galileo (TNG) and at the European Southern Observatory (ESO), La Silla, Chile and on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).Table 1 is available in electronic form at http://www.aanda.org