%0 Generic %1 Bournaud2011 %A Bournaud, Frederic %A Dekel, Avishai %A Teyssier, Romain %A Cacciato, Marcello %A Daddi, Emanuele %A Juneau, Stephanie %A Shankar, Francesco %D 2011 %K accretion agn blackhole cold flows %T Black Hole growth and AGN obscuration by instability-driven inflows in high-redshift disk galaxies fed by cold streams %U http://arxiv.org/abs/1107.1483 %X Disk galaxies at high redshift maintain high gas surface densities, due to continuous feeding by intense cold streams. This leads to a violent gravitational instability involving transient features and giant clumps. The instability is self-regulated at a Toomre stability parameter Q~1. Torques between the perturbations drive angular momentum out and mass in. The inflow down the potential gradient provides the energy for keeping strong turbulence at the Q~1 level while compensating for dissipative losses. Analytic estimates and simulations with parsec-scale resolution predict, for a gas-rich disk galaxy of 10^11 Msun at z=2, an average inflow rate ~10 Msun/yr into the central kpc. The inflow rate scales with disk mass and (1+z)^3/2. This inflow is responsible for the growth of a bulge, while a fraction ~10^-3*(1+z) of it needs to accrete onto a central black hole obeying the observed scaling relations. A galaxy of 10^11 Msun z~2 hosts a black hole of ~10^8 Msun, accreting on average in sub-Eddington mode with moderate luminosity L_X~10^42-43 erg/s, but possibly accompanied by bright Eddington-limited episodes. In early-forming massive systems at z~6, the same process may feed 10^9 Msun black holes from seeds of <10^5Msun at z~10. The inflow also generates high gas column densities that can severely obscure AGN in high-redshift disks.

@misc{Bournaud2011, abstract = { Disk galaxies at high redshift maintain high gas surface densities, due to continuous feeding by intense cold streams. This leads to a violent gravitational instability involving transient features and giant clumps. The instability is self-regulated at a Toomre stability parameter Q~1. Torques between the perturbations drive angular momentum out and mass in. The inflow down the potential gradient provides the energy for keeping strong turbulence at the Q~1 level while compensating for dissipative losses. Analytic estimates and simulations with parsec-scale resolution predict, for a gas-rich disk galaxy of 10^11 Msun at z=2, an average inflow rate ~10 Msun/yr into the central kpc. The inflow rate scales with disk mass and (1+z)^{3/2}. This inflow is responsible for the growth of a bulge, while a fraction ~10^{-3}*(1+z) of it needs to accrete onto a central black hole obeying the observed scaling relations. A galaxy of 10^11 Msun z~2 hosts a black hole of ~10^8 Msun, accreting on average in sub-Eddington mode with moderate luminosity L_X~10^{42-43} erg/s, but possibly accompanied by bright Eddington-limited episodes. In early-forming massive systems at z~6, the same process may feed 10^9 Msun black holes from seeds of <10^5Msun at z~10. The inflow also generates high gas column densities that can severely obscure AGN in high-redshift disks. }, added-at = {2011-07-09T08:39:04.000+0200}, author = {Bournaud, Frederic and Dekel, Avishai and Teyssier, Romain and Cacciato, Marcello and Daddi, Emanuele and Juneau, Stephanie and Shankar, Francesco}, biburl = {https://www.bibsonomy.org/bibtex/2689d2de56c99c7f96ef7990f3b69f667/miki}, description = {[1107.1483] Black Hole growth and AGN obscuration by instability-driven inflows in high-redshift disk galaxies fed by cold streams}, interhash = {b3add6f1462d8cc23c1b343574a3618f}, intrahash = {689d2de56c99c7f96ef7990f3b69f667}, keywords = {accretion agn blackhole cold flows}, note = {cite arxiv:1107.1483Comment: ApJL submitted}, timestamp = {2011-07-09T08:39:04.000+0200}, title = {Black Hole growth and AGN obscuration by instability-driven inflows in high-redshift disk galaxies fed by cold streams}, url = {http://arxiv.org/abs/1107.1483}, year = 2011 }