Gamma-rays from interactions of stars with active galactic nucleus jets

Abstract

We have developed a model for gamma-ray emission in jets of active galactic nuclei in which particle acceleration takes place at a shock in the relativistic jet plasma due to a massive star in the central region of the host galaxy moving through the jet. The gamma-rays are produced in a pair-Compton cascade in the radiation field of the star initiated by accelerated electrons. Our model may account for the observed GeV to TeV gamma-ray spectrum and variability of Markarian 421 and other blazars detected by the EGRET instrument on the Compton Gamma Ray Observatory. © 1997 RAS.