In the present-day universe, the masses of giant black holes are
correlated with the luminosities, masses, and velocity dispersions
of their host galaxies. This empirical correlation of phenomena on
widely different scales suggests that the growth of black holes and
the evolution of galaxies are closely linked. Understanding the
origin of this correlation is a major challenge for cosmological
models and is believed to hold a key to solving several astrophysical
problems. With high S/N Keck spectra and HST images, I will present
direct measurements of the scaling relations between black hole mass
and host galaxy properties at z=0.36 and z=0.57. By comparing these
relations with those of local quiescent and Seyfert galaxies,
I will show that the relations evolved significantly in the last 6
billion years, indicating that the growth of black hole predates the
final bulge assembly, at the mass scales of sigma=~170 km/s.
Selection bias and the mass-dependency of the evolution will b
discussed.
At the end of the talk, I will present the first Chandra result from
AMUSE-Virgo (AGN Multi-wavelength Survey of Early-type galaxies in
Virgo). Low level activities of supermassive black holes
(-8.4 < log (Lx/L_Edd) < -5.8) were detected in 16 out of 32
galaxies, and their kinetic energy output is consistent with models
for cosmic sturcture formation (AGN radio mode).