Exploring the non-thermal Universe


Cas-A


One of the major open questions remaining in physics is the origin of cosmic rays, discovered in 1912 by Victor Hess.

Favoured candidates for the origin and acceleration of cosmic rays are supernova remnants.

The image shows the radio-continuum emission of Cassiopeia A, the remnant of a supernova explosion ca. 300 years ago. Today it is one of the strongest radio sources in the sky.


Ground-based Imaging Atmospheric Cherenkov Telescopes have become the most efficient experimental technique for the observation of cosmic gamma rays in the TeV energy range. The gamma rays trace back to cosmic accelerators which may also be responsible for the creation and acceleration of the charged cosmic rays.
CT3 after sunset