Matthias Fuessling HU Berlin

Search for Pulsed TeV Gamma-Ray Emission from Pulsars with H.E.S.S. (pdf)

Over 1,500 objects, emitting pulsed radiation in the radio band, have been found so far in the universe. These pulsars are commonly regarded as neutron stars with a high magnetic field and a rotation period in the range of 2 ms to 8 s. For some of them, emission has been observed up to the order of GeV, the high-energy gamma-ray regime. Numerous theories for the acceleration mechanism exist, predicting a cut-off in the energy spectrum at several 10 GeV . One possible way to access this so far unobserved energy range is through Imaging Atmospheric Cherenkov Telescopes (IACTs). These experiments use the earth's atmosphere as a calorimeter and detect the Cherenkov radiation of the induced air showers at the ground level. The H.E.S.S. project, situated in Namibia, is one of these systems, sensitive for gamma-rays from 100 GeV to 100 TeV. First results are presented as well as new approaches to improve the sensitivity at low energies and thus to access the cut-off region.