Probing the M-sigma Relation in the Non-Local Universe Using Red QSOs
  We describe a method to measure the M-sigma relation in the non-local
universe using dust-obscured QSOs. We present results from a pilot sample of
nine 2MASS red QSOs with redshifts 0.14<z<0.37. We find that there is an offset
(0.8 dex, on average) between the position of our objects and the local
relation for AGN, in the sense that the majority of red QSO hosts have lower
velocity dispersions and/or more massive BHs than local galaxies. These results
are in agreement with recent studies of AGN at similar and higher redshifts.
This could indicate an unusually rapid growth in the host galaxies since z~0.2,
if these objects were to land in the local relation at present time. However,
the z>0.1 AGN (including our sample and those of previous studies) have
significantly higher BH mass than those of local AGN, so a direct comparison is
not straightforward. Further, using several samples of local and higher-z AGN,
we find a striking trend of an increasing offset with respect to the local
M-sigma relation as a function of AGN luminosity, with virtually all objects
with log(L_5100/erg s^-1) > 43.6 falling above the relation. Given the
relatively small number of AGN at z>0.1 for which there are direct measurements
of stellar velocity dispersions, it is impossible at present to determine
whether there truly is evolution in M-sigma with redshift. Larger, carefully
selected samples of AGN are necessary to disentangle the dependence of M-sigma
on mass, luminosity, accretion rates, and redshift.
