graduate

An unprecedented view of the prototypical outflow in NGC 5548

TYPEAstrophysics Seminar
Speaker:Prof. Nahum Arav
Affiliation:Virginia Tech, Department of Physics
Date:02.07.2014
Time:14:30 - 15:30
Location:Lidow 620
Abstract:

Outflows from Active Galactic Nuclei (AGN) are thought to influence the evolution of their host galaxies and Super Massive Black Holes (SMBH). Our deep multiwavelength campaign on NGC 5548 revealed an unusual strong X-ray obscuration. The resulting dramatic decrease in ionizing illumination allowed us to construct an unprecedented physical, spatial and temporal picture for the long-studied AGN outflow in this object. A simple model based on a fixed total column-density absorber, reacting to changes in ionizing illumination, matches the very different ionization states seen in five spectroscopic epochs spanning 16 years. Four outflow components are situated between 5-70 parsec from the SMBH and two are further than 100 parsec. The disparate relationship of the observed X-ray and UV flux between different epochs, makes our physical model a leading contender for interpreting trough variability data of quasar outflows.