Black hole scaling relationships: New results from reverberation mapping and Hubble space telescope imaging

We investigate the results of reverberation-mapping mass measurements and two-dimensional (2-D) decompositions of high-resolution host galaxy images in the context of black hole scaling relationships. We present new monitoring data leading to an improved black hole mass measurements for the nearby Seyfert galaxy NGC4151. We also present new monitoring data for the well-studied NGC5548, which show the active galactic nucleus (AGN) in the lowest luminosity state during a monitoring campaign. We show that the mass derived from this low state is consistent with previous mass measurements, and that the virial relationship previously discovered between the width of the broad lines and their time lags relative to the continuum flux still holds.; We also present complete, 2-D galaxy decompositions for 29 of the 36 objects in the reverberation-mapped sample. We create PSF-subtracted images of the host galaxies and measure the starlight contribution to the luminosity measurements from the original monitoring programs. Accounting for this contribution, we revisit the radius-luminosity relationship for AGNs and find a reduced scatter and a slope of alpha ≈ 0.5 that holds over 5 decades in luminosity. This slope is consistent with the naive expectation that all AGNs are simply scaled models of each other.; Finally, we use the galaxy model parameters to investigate several black hole mass scaling relationships with host galaxy properties, namely the black hole mass - bulge luminosity relationship (MBH - LBulge), the black hole mass - bulge mass ( MBH - MBulge) relationship, and the black hole mass - Sersic index (MBH - n) relationship. We find tight correlations for the MBH - LBulge and MBH - MBulge relationships, but these results only marginally agree with previous studies. Rather, they point to an increased black hole mass fraction at lower bulge luminosities and masses than was previously seen. Additionally, we find no evidence for the MBH - n relationship in this sample of objects. We discuss several differences between the methods employed by various studies and how these may lead to the observed discrepancies in the results.