http://arxiv.org/abs/1402.4482
Recent observations have revealed nuclear outflows in high-redshift, star forming galaxies. We study outflows driven by Active Galactic Nuclei (AGNs) using high- resolution simulations of idealized z=2 isolated disk galaxies. Episodic accretion events lead to outflows with velocities >1000 km/s and mass outflow rates up to the star formation rate (several tens of Msun/yr). Outflowing winds escape perpendicular to the disk with wide opening angles, and are typically asymmetric (i.e. unipolar) because dense gas above or below the AGN in the resolved disk inhibits outflow. Owing to rapid variability in the accretion rates, outflowing gas may be detectable even when the AGN is effectively “off.” The highest velocity outflows are concentrated within 2-3 kpc of the galactic center during the peak accretion. With our purely thermal AGN feedback model — standard in previous literature — the outflowing material is mostly hot (10^6 K) and diffuse (nH<10^(-2) cm-3), but includes a cold component entrained in the hot wind. Despite the powerful bursts and outflow rates near the star formation rate, AGN feedback has little effect on the dense gas in the galaxy disk.
J. Gabor and F. Bournaud
Thu, 20 Feb 14
43/52