Data Analysis and Interpretation

We analyse data taken with the MAGIC and FACT telescopes to investigate galactic and extragalactic sources of VHE gamma-rays. In the past, we made major contributions to the first detection of unexpected VHE emission from a Pulsar (PhD Thesis of Michael Rissi) and search for fundamental physics processes like Dark Matter annihilation (PhD Thesis of Sabrina Stark Schneebeli) and Quantum Gravity Effects like violation of Lorentz Invariance (A. Biland was convenor of the Fundamental Physics working group of MAGIC 2003-2010)

Taking into account the reduced size of the group and the advent of FACT, we currently concentrate fully on Active Galactic Nuclei.These consist from Supermassive Black Holes that, opposite to the Black Hole in the center of the milkyway, are currently consuming large amount of mass. In this process, high energetic plasma jets are emitted. If such a jet is pointing towards us, highly variable VHE flux can be measured. In the PhD thesis of Dorothee Hildebrand, two VHE emitting Radio Galaxies were found, doubling the number of the known such objects. In the ongoing PhD thesis of Axel Arbet-Engels, some of the most extreme Active Galactic Nuclei are investigated. One result is, that extreme state seems to be only a short temporal state for some of these objects.

With the rather small FACT telescope, we execute since 2011 the first unbiased long-term observation of the brightest variable VHE objects. This does not only allow to alert the community within minutes of bright outbursts, but also to investigate correlations between the VHE flux and other energies and time dependent effects.

In addition, we also contribute to the improvements of analysis techniques. E.g. the PhD thesis of Sebastian Commichau showed that the geomagnetic field has measurable effects on the air-shower development. This affects the reconstructed flux and energy measurements. The thesis of Max Ahnen included a investigation how much results can be improved applying Bayesian statistics instead of the frequentists statistics used so far.