AGN mass estimates in large spectroscopic surveys: the effect of host
  galaxy light
  Virial-based methods for estimating active supermassive black hole masses are
now commonly used on extremely large spectroscopic quasar catalogues. Most
spectral analyses, though, do not pay enough attention to a detailed continuum
decomposition. To understand how this affects virial mass estimate results, we
test the influence of host galaxy light on them, along with Balmer continuum
component. A detailed fit with the new spectroscopic analysis software QSFit
demonstrated that the presence or absence of continuum components do not affect
significantly the virial-based results for our sample. Taking or not in
consideration a host galaxy component, instead, affects the emission line
fitting in a more pronounced way at lower redshifts, where in fact we observe
dimmer quasars and more visible host galaxies.
