Experimental Astroparticle Physics — Research

We study the high-energy Universe in gamma-rays. To measure these gamma-rays, we are involved in the most sensitive array of imaging atmospheric Cherenkov telescopes to date, the High Energy Stereoscopic System H.E.S.S. and the next generation instrument, the Cherenkov Telescope Array Obervatory CTAO.

Photo: H.E.S.S. Collaboration
The supernova remnant RX J1713.7-3946

Gamma-Ray Astronomy

In Gamma-Ray Astronomy we observe the high-energy end of the electromagnetic spectrum and thereby the most violent processes of the Universe. Being established as an accessible observation window only since a few decades, today we have a wealth of gamma-ray data that allows in-depth studies of the Milky Way and the extragalactic sky at very high energies. Our group in Potsdam is active in the analysis and modelling of gamma-ray sources and diffuse emission.

On Galactic scales, our main focus lies on the global properties of the Milky Way: we study the properties of the gamma-ray source populations and perform simulations of the gamma-ray sources in the Milky Way. The second component of gamma-ray emission besides the sources is the diffuse emission that is to be found along the Galactic Plane. In Potsdam, we measure the large-scale diffuse gamma-ray emission  and investigate the interplay between diffuse emission and the gamma-ray source populations.

On extragalactic scales, we also search for transient phenomena like gamma-ray bursts, which have just recently been observed for the first time ground based by the MAGIC and H.E.S.S. telescopes, and we are actively involved in the search for electromagnetic counterparts of gravitational-wave events.

For information on Bachelor, Master, and Ph.D. theses, see here.

Photo: H.E.S.S. Collaboration
The supernova remnant RX J1713.7-3946
das Cherenkov Telescope Array
Photo: G. Perez, SMM, IAC
The Cherenkov Telescope Array Observatory

The CTAO Transients Handler 

The University of Potsdam has the responsibility of developing the Transients Handler for the Cherenkov Telescope Array Observatory (CTAO). CTAO is currently being built on two sites in the Northern hemisphere in La Palma and on the Southern hemisphere in Chile and will be the next-generation instrument measuring very-high-energy gamma-rays. Transient science will be a key science project for CTAO and the Transients Handler is the centrepiece of these efforts. Its role is to connect CTAO to facilities all over the world. Via a broker system it receives alerts on a transient phenomenon from satellites like SWIFT or Fermi, observatories like Vera C. Rubin Observatory, or from gravitational-wave or neutrino instruments, it processes and filters these alerts, and initiates follow-up observations with CTAO.

More information on the Cherenkov Telescope Array Observatory can be found here. For information on Bachelor, Master, and Ph.D. theses, see here.

das Cherenkov Telescope Array
Photo: G. Perez, SMM, IAC
The Cherenkov Telescope Array Observatory
Photo: Arnim Balzer
A gamma-ray seen in the H.E.S.S. cameras

Modern Tools for Data Analysis

Ground-based gamma-ray astronomy relies heavily on complex data analysis procedures. Our passion is pushing the limits of what is currently possible: the analysis of emission regions much more extended than the field of view of the telescopes, the extraction of information from limited and highly biased samples of data, detections at the sensitivity limit.

To reach our goals we work on the development of new techniques for the analysis of very-high-energy gamma-ray data at various steps of the data analysis spanning from reconstruction of individual photon properties based on air-shower images to the high-level treatment of catalog data. Besides classical approaches we also employ modern technologies like deep-learning techniques to maximise the information content extractable from our data.

For information on Bachelor, Master, and Ph.D. theses, see here.

Photo: Arnim Balzer
A gamma-ray seen in the H.E.S.S. cameras
Photo: Stefan Klepser
The H.E.S.S. Collaboration during its spring meeting 2014 in Potsdam