Description:

Quasars, and their extreme variety "Blazars", are the brightest examples of Active Galactic Nuclei (AGN) which are powered by supermassive black holes that are voraciously feeding on material flowing into the center of the galaxy.  In addition to their tremendous output of light across the electromagnetic spectrum, some AGN also have collimated outflows of highly energetic plasma which stream away from the center of the galaxy at apparent speeds greater than the speed of light.  In their most spectacular form, these relativistic jets can extend for hundreds of thousands of light-years, well outside the host galaxy, to inflate giant radio lobes.  I use interferometric networks of radio telescopes across the globe to image and monitor these jets very near their origin in the supermassive black hole, accretion disk system.  Our goal is to better understand the structure of these jets and how they are accelerated and collimated.  This work involves disentangling the effects of relativistic motion near our line of sight to uncover the underlying properties of the jet itself.

Daniel Homan, Professor, Denison University

Host: Farhad Zadeh