Measuring AGN feedback parameters from seyfert galaxy outflows


We present results of an on-going program to measure AGN feedback in Seyfert galaxies using integral-field spectroscopy and adaptive optics at Keck Observatory and VLT. Our integral-field observations are revealing AGN-driven outflows of ionized gas in Seyfert galaxies. By resolving the inner 10-40 parsecs, we are successfully modeling them as biconical structures, in which the ionized gas first accelerates and then decelerates. The model parameters provide crucial information on the orientation, geometry and kinematics of the outflows, which is used to estimate mechanical feedback from the AGN: mass and kinetic energy transferred to the interstellar medium. Mass outflow rates can be 102-104 times greater than accretion rates, but in some cases, they are comparable to the estimated inflow rates to the central 10-25 pc, suggesting that the outflows may remove a considerable amount of the infalling gas before it reaches the accretion disk. In half of the AGN measured so far, the kinetic energy of the outflows appears sufficient to provide the eagerly-sought AGN feedback invoked to explain fundamental galaxy properties such as the M BH-σ* relation (0.5-5 L bol). The other AGN, which lack powerful outflows, also have weaker and more compact radio jets. © 2013 International Astronomical Union.

Publication Title

Proceedings of the International Astronomical Union