High Energy Stereoscopic System (H.E.S.S.) is a system of imaging atmospheric Cherenkov telescopes (IACTs) for the investigation of cosmic gamma rays in the photon energy range of 0.03 to 100 TeV, located in the Khomas Region of Namibia and operating since 2002. The acronym was chosen in honour of Victor Hess, who discovered the extraterrestrial origin of cosmic rays.

The name also emphasizes two main features of the installation, namely the simultaneous observation of air showers with several telescopes, under different viewing angles, and the combination of telescopes to a large system to increase the effective detection area for gamma rays. H.E.S.S. permits the exploration of gamma-ray sources with intensities at a level of a few thousandth parts of the flux of the Crab Nebula.

The four smaller telescopes were constructed as the first phase of the H.E.S.S. project, with the first of the four telescopes beginning operation in Summer 2002; all four were operational in December 2003, with the project officially inaugurated in 2004.

In 2016, the HESS collaboration reported deep gamma ray observations which show the presence of petaelectronvolt-protons originating from Sagittarius A*, the supermassive black hole at the centre of the Milky Way, and therefore should be considered as a viable alternative to supernova remnants as a source of petaelectronvolt galactic cosmic rays.

See also

  • Werner Hofmann (physicist)
  • Major Atmospheric Cerenkov Experiment Telescope

References

  • High Energy Stereoscopic System Project (H.E.S.S.) on the internet
  • Nature: High energy particle acceleration in the shell of a supernova remnant
  • Science: A new population of very high energy gamma-ray sources in the Milky Way
  • New Scientist: Number of very high-energy gamma ray sources doubles
  • Aspera European network portal
  • HESS experiment record on INSPIRE-HEP