Physics of Particle and Radiation Detection

The measurement techniques relevant to astroparticle physics are rather diverse. The detection of astroparticles is usually a multistep process. In this field of research, particle detection is mostly indirect. It is important to identify the nature of the astroparticle in a suitable interaction process. The target for interactions is, in many cases, not identical with the detector that measures the interaction products. Cosmic-ray muon neutrinos, for example, interact via neutrino–nucleon interactions in the antarctic ice or in the ocean, subsequently producing charged muons. These muons suffer energy losses from electromagnetic interactions in the ice (water), in which, among others, Cherenkov radiation is produced. The Cherenkov light is recorded, via the photoelectric effect, by photomultipliers. This is then used to reconstruct the energy and the direction of incidence of the muon, which is approximately identical to the direction of incidence of the primary neutrino.