Constraints on the multi-TeV particle population in the Coma Galaxy Cluster with H.E.S.S. observations
Abstract
The H.E.S.S. (High Energy Stereoscopic System) telescopes observed Coma for ~8hr in a search for gamma-ray emission at energies }1TeV. The large 3.5deg FWHM field of view of H.E.S.S. is ideal for viewing a range of targets at various sizes including the Coma cluster core, the radio-relic (1253 275) and merger/infall (NGC 4839) regions to the southwest, and features greater than deg away.
No evidence for point-like nor extended TeV gamma-ray emission was found and upper limits to the TeV flux F(E) for E}1, }5, and }10TeV were set for the Coma core and other regions. Converting these limits to an energy flux E^2F(E) the lowest or most constraining is the E}5TeV upper limit for the Coma core (0.2deg radius) at ~8Crab flux units or ~10^{-13}ph cm^{-2} s^{-1}.