To appear in "The Central Kpc of Starbursts
and AGN", ed. J. H. Knapen, J. E. Beckman, I. Shlosman & T. J. Mahoney;
astro-ph/0107134
For a postscript version of the article, click
here.
RELATIONSHIP OF BLACK HOLES TO BULGES
David Merritt and Laura Ferrarese
Department of
Physics and Astronomy,
Rutgers University,
New Brunswick,
NJ, USA
Abstract. Supermassive black holes appear to be uniquely
associated with galactic bulges.
The mean ratio of black hole mass to bulge mass was until recently
very uncertain, with ground-based, stellar kinematical data
giving a value for
<M
/
Mbulge> roughly an order
of magnitude larger than other techniques.
The discrepancy was resolved with the discovery of the
M -
relation,
which simultaneously established a tight corrrelation between black
hole mass and bulge velocity dispersion, and confirmed that the
stellar kinematical mass estimates were systematically too large due to
failure to resolve the black hole's sphere of influence.
There is now excellent agreement between the various techniques
for estimating
<M /
Mbulge>,
including dynamical mass estimation in quiescent galaxies;
reverberation mapping in active galaxies and quasars;
and computation of the mean density of compact objects based on
integrated quasar light. All techniques now give
<M /
Mbulge>
10-3 and
3 × 105
M
/
Mpc-3. Implications of the
M -
relation for the formation
of black holes are discussed.
Table of Contents
