Relativistic Beaming in Gamma-ray Blazars
Abstract
Numerous lines of evidence, both theoretical and observational, suggest that the gamma-ray emission from most blazars is highly relativistically beamed. With the large volume of high quality data being provided by Fermi, it is now possible to examine the statistical effects of relativistic beaming in large samples of AGNs and gain insight into their high-energy photon production mechanisms. The MOJAVE program is currently monitoring over 250 AGN with the VLBA at 15 GHz to examine the relation between parsec-scale jet activity and gamma-ray emission. The sample has been constructed to include complete radio-flux-density- limited and gamma-ray-flux-limited AGN subsamples, as well as lower-luminosity radio galaxies with compact radio cores. The observational data on the sample now includes extensive information on the long-term jet kinematics, kpc-scale radio and X-ray structure, radio variability, and gamma-ray properties. We have identified several important connections in the MOJAVE sample between radio and gamma-ray luminosity, apparent jet speed, and jet power that can be best interpreted within the framework of the unified model and relativistic beaming effects. We discuss the complex selection biases that determine the make-up of the Fermi LAT AGN catalog and their implications for blazar demographic studies.
- Publication:
-
AAS/High Energy Astrophysics Division #11
- Pub Date:
- March 2010
- Bibcode:
- 2010HEAD...11.3004L