H.E.S.S. (High Energy Stereoscopic System) collaboration (since 1998)


Name of the project (years)

H.E.S.S. (High Energy Stereoscopic System) collaboration (since 1998)

Short description

YerPhI is among the founding members of H.E.S.S. (High Energy Stereoscopic System) collaboration. The collaboration operates a system of Imaging Atmospheric Cherenkov Telescopes (IACTs) that investigates cosmic gamma rays in the energy range from 10s of GeV to 10s of TeV. The H.E.S.S. is located in the Khomas Highland in Namibia, at an altitude of 1800m above sea level. It is an array of five IACTs, with four telescopes (HESS I) of  12m diameter arranged in a square of 120m side length and one telescope (HESS II) of  28m diameter in the center of array. First 4 telescopes (Phase I) were operational since 2004 and system of 5 telescopes (Phase II) – since 2012. 

The H.E.S.S. observatory is operated by collaboration, which is consortium of over 40 institutions from 13 countries. As of May 2020, the H.E.S.S. collaboration has published over 180 research articles in high-impact scientific journals, including ‘Nature’ and ‘Science’ journals.

In 2006, H.E.S.S. was awarded the Descartes Prize of the European Commission and in 2010 the Rossi Prize of the American Astronomical Society. In a survey in 2006, H.E.S.S. was ranked the 10th most influential observatory worldwide.

Person in charge



Current members of the HESS collaboration working at AANL (YerPhI) is V. Sahakian, and other members of the group are G. Papyan and M. Jamkochyan.



contact person

V. Sahakian

MoU(If applicable for internal website)

The Agreement on Continuation of H.E.S.S. collaboration up to 1, October of 2022 was signed in 2019. 

corresponding link to the collaborating institutions or project