Messages from a Black Hole

Abstract

Markarian (Mrk) 421 is a blazar, an Active Galactic Nucleus (AGN) with its jets aligned to our linof- sight. It is therefore possible to detect very high energetic γ-rays, which are produced by ultrarelativitic moving particles inside the jets. In this work this high energetic γ-radiation recorded by the MAGIC-I Cherenkov telescope on the Canary Island of La Palma is analysed. The short-term and long-term variability is examined as well as the spectral shape. Additionally, a periodicity search is performed for the resulting light curve. Finally, the MAGIC-I result is compared to lthe results of instruments measuring in other energy bands to draw conclusions on the acceleration mechanisms inside Mrk 421.