Detection of TeV γ-ray emission from the shell-type supernova remnant RX J0852.0-4622 with HESS

We report the detection of TeV gamma-rays from the shell-type supernova remnant RXJ0852.0-4622 with data of 3.2 h of live time recorded with HESS in February 2004. An excess of ( 700 +/- 60) events from the whole remnant with a significance of 12 sigma was found. The observed emission region is clearly extended with a radius of the order of 1 degrees and the spatial distribution of the signal correlates with X-ray observations. The spectrum in the energy range between 500 GeV and 15 TeV is well described by a power law with a photon index of Gamma = 2.1 +/- 0. 1(stat) +/- 0.2(syst) and a differential flux at 1 TeV of (phi 1TeV) = (2.1 +/- 0.2(stat) +/- 0.6(syst)) x 10(-11) cm(-2) s(-1) TeV-1. The integral flux above 1 TeV was measured to be Phi(E > 1TeV) = (1.9 +/- 0.3(stat) +/- 0.6(syst)) x 10(-11) cm(-2) s(-1), which is at the level of the flux of the Crab nebula at these energies. More data are needed to draw firm, conclusions on the magnetic field in the remnant and the type of the particle population creating the TeV gamma-rays.