Black hole mass estimates from reverberation mapping and from spatially resolved kinematics

Black hole (BH) masses that have been measured by reverberation mapping in active galaxies fall significantly below the correlation between bulge lumi nosity and BH mass determined from spatially resolved kinematics of nearby normal galaxies. This discrepancy has created concern that one or both tech niques suffer from systematic errors. We show that BH masses from reverbera tion mapping are consistent with the recently discovered relationship betwe en BH mass and galaxy velocity dispersion. Therefore, the bulge luminositie s are the probable source of the disagreement, not problems with either met hod of mass measurement. This result underscores the utility of the BH mass -velocity dispersion relationship. Reverberation mapping can now be applied with increased confidence to galaxies whose active nuclei are too bright o r whose distances are too large for BH searches based on spatially resolved kinematics.