Max Planck Institute for Radio Astronomy/Argelander Institute for Astronomy Main Colloquium
Titel: Active galaxies: a radio and gamma-ray perspective
Speaker: Professor Dhruba Saikia, Tata Institute of Fundamental Research, Pune, India
Active galaxies, which include both starburst galaxies and active galactic nuclei (AGN), are among the most enigmatic objects in our Universe. They emit across the electromagnetic spectrum and there is also increasing evidence of detection of neutrinos from some of them. This presentation will briefly introduce the different kinds of active galaxies, and discuss their emission at the highest energies, namely gamma rays, along with their radio properties. Although the bulk of the extragalactic gamma ray sources have been observed to be associated with blazars, which are believed to have their jets inclined at small angles to the line of sight, a wide and rich variety of active galaxies in significant numbers have been found to be associated with gamma ray sources in recent years. Some of these recent results and their implications will be discussed.