SIMBAD references

We analyse a sample of 32 galaxies for which a dynamical estimate of the mass of the hot stellar component, M_bulge, is available. For each of these galaxies, we calculate the mass of the central black hole, M_ø, using the tight empirical correlation between M_ø and bulge stellar velocity dispersion. The frequency function N[log(M_. M_bulge)] is reasonably well described as a Gaussian with <log(M_. M_bulge) ≳ -2.90 and standard deviation ∼0.45; the implied mean ratio of black hole mass to bulge mass is a factor of ∼5 smaller than generally quoted in the literature. We present marginal evidence for a lower, average black hole mass fraction in more massive galaxies. The total mass density in black holes in the local Universe is estimated to be ∼ 5x10⁵M_solarMpc^–3, consistent with that inferred from high-redshift (z∼2) active galactic nuclei.