Revisiting the Scaling Relations of Black Hole Masses and Host Galaxy
  Properties
  New kinematic data and modeling efforts in the past few years have
substantially expanded and revised dynamical measurements of black hole masses
(Mbh) at the centers of nearby galaxies. Here we compile an updated sample of
72 black holes and their host galaxies, and present revised scaling relations
between Mbh and stellar velocity dispersion (sigma), V-band luminosity (L), and
bulge stellar mass (Mbulge), for different galaxy subsamples. Our best-fitting
power law relations for the full galaxy sample are log(Mbh) = 8.32 +
5.64*log(sigma/200 kms), log(Mbh) = 9.23 + 1.11*log(L/10^{11} Lsun), and
log(Mbh) = 8.46 + 1.05*log(Mbulge/10^{11} Msun). A log-quadratic fit to the
Mbh-sigma relation with an additional term of beta_2*[log(sigma/200 kms)]^2
gives beta_2 = 1.68 +/- 1.82 and does not decrease the intrinsic scatter in
Mbh. When the early- and late-type galaxies are fit separately, we obtain
similar slopes of 5.20 and 5.06 for the Mbh-sigma relation but significantly
different intercepts -- Mbh in early-type galaxies are about 2 times higher
than in late types at a given sigma. Within early-type galaxies, our fits to
Mbh(sigma) give Mbh that is about 2 times higher in galaxies with central core
profiles than those with central power-law profiles. Our Mbh-L and Mbh-Mbulge
relations for early-type galaxies are similar to those from earlier
compilations. When the conventional quadrature method is used to determine the
intrinsic scatter in Mbh, our dataset shows weak evidence for increased scatter
at Mbulge < 10^{11} Msun or L_V < 10^{10.3} Lsun, while the scatter stays
constant for 10^{11} < Mbulge < 10^{12.3} Msun and 10^{10.3} < L_V < 10^{11.5}
Lsun. A Bayesian analysis indicates a larger sample of Mbh measurements would
be needed to detect any statistically significant trend in the scatter with
galaxy properties.
