Ground based gamma-ray observations with H.E.S.S.

Olaf Reimer (Stanford)

The H.E.S.S. experiment, a system of four imaging atmospheric Cherenkov telescopes, is located in the Khomas Highlands of Namibia. By applying the stereoscopic technique, the telescope array reaches an energy threshold of about 100 GeV for the detection of energetic gamma-rays with a currently unprecedented sensitivity. A large field of view of the telescopes and the angular resolution better than 0.1 deg make the instrument suitable not only for point source studies, but for detailed investigation of extended sources. During the first years of operation, H.E.S.S. has already provided the largest number of VHE gamma-ray source detection to date. I will give an overview of the observational technique, the H.E.S.S. experiment as currently in operation, and review the impressive results from the first years of observation by concentrating on the novel accomplishments by H.E.S.S. at the most energetic end of the electromagnetic spectrum.