John Kormendy (Department of Astronomy, University of Texas at Austin),
Karl Gebhardt (UCO/Lick Observatory), and
Douglas Richstone (Department of Astronomy, University of Michigan)
New detections of supermassive black hole (BH) candidates are used to update the observed correlation between BH mass M_BH and the luminosity L_bulge of the bulge component of the host galaxy. Our main purpose is to test whether the correlation is real or just the upper envelope of a distribution that extends to smaller M_BH. We also illustrate the following conclusions:
1 -- BH mass correlates much better with bulge luminosity than with the total luminosity of the galaxy.
2 -- BH mass correlates with the luminosity of the high-density central component in disk galaxies independent of whether that component is a classical bulge (essentially a mini-elliptical) or a ``pseudobulge'' (believed to form via inward transport of disk material). This conclusion is based on only three pseudobulges, so it needs to be checked.
3 -- The BH mass correlates with the velocity dispersion of the bulge component outside the region influenced by the BH. That is, it correlates with the depth of the potential well in which it lives.
Our conclusions are consistent with the hypothesis that (pseudo)bulge formation and BH feeding are closely connected. To first order, present data do not show any dependence of M_BH on the details of whether BH feeding happens rapidly during a collapse or slowly via secular evolution of the disk.
This work was supported by HST data analysis funds through grants GO-02600.01-87A and GO-07388.01-96A. KG is supported by NASA through Hubble Fellowship grant HF-01090.01-97A awarded by STScI. DR is supported by NASA grant NAG-8238.
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