Min-Su Shin, Jeremiah P. Ostriker, Luca Ciotti
We investigate how environmental effects by gas stripping alter the growth of
a super massive black hole (SMBH) and its host galaxy evolution, by means of 1D
hydrodynamical simulations that include both mechanical and radiative AGN
feedback effects. By changing the truncation radius of the gas distribution
(R_t), beyond which gas stripping is assumed to be effective, we simulate
possible environments for satellite and central galaxies in galaxy clusters and
groups. The continuous escape of gas outside the truncation radius strongly
suppresses star formation, while the growth of the SMBH is less affected by gas
stripping because the SMBH accretion is primarily ruled by the density of the
central region. As we allow for increasing environmental effects - the
truncation radius decreasing from about 410 to 50 kpc - we find that the final
SMBH mass declines from about 10^9 to 8 x 10^8 Msol, but the outflowing mass is
roughly constant at about 2 x 10^10 Msol. There are larger change in the mass
of stars formed, which declines from about 2 x 10^10 to 2 x 10^9 Msol, and the
final thermal X-ray gas, which declines from about 10^9 to 5 x 10^8 Msol, with
increasing environmental stripping. Most dramatic is the decline in the total
time that the objects would be seen as quasars, which declines from 52 Myr (for
R_t = 377 kpc) to 7.9 Myr (for R_t = 51 kpc). The typical case might be
interpreted as a red and dead galaxy having episodic cooling flows followed by
AGN feedback effects resulting in temporary transitions of the overall galaxy
color from red to green or to blue, with (cluster) central galaxies spending a
much larger fraction of their time in the elevated state than do satellite
galaxies.(Abridged)
View original:
http://arxiv.org/abs/1003.1108
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