AGN feedback and triggering of star formation in galaxies. (arXiv:1209.1480v1 [astro-ph.GA]):
Feedback from the central black hole in active galactic nuclei (AGN) may be
responsible for establishing the observed MBH-sigma relation and limiting the
bulge stellar mass of the host galaxy. Here we explore the possibility of AGN
feedback triggering star formation in the host galaxy. We consider a shell of
dusty gas, driven outwards by radiation pressure, and analyse its
escape/trapping condition in the galactic halo for different underlying dark
matter potentials. In the isothermal potential, we obtain that the standard
condition setting the observed MBH-sigma relation is not sufficient to clear
gas out of the entire galaxy; whereas the same condition is formally sufficient
in the case of the Hernquist and Navarro-Frenk-White profiles. The squeezing
and compression of the inhomogeneous interstellar medium during the ejection
process can trigger star formation within the feedback-driven shell. We
estimate the resulting star formation rate and total additional stellar mass.
In this picture, new stars are formed at increasingly larger radii and
successively populate the outer regions of the host galaxy. This characteristic
pattern may be compared with the observed 'inside-out' growth of massive
galaxies.
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