Observation of the giant radio galaxy M87 at TeV energies with H.E.S.S
  The giant radio galaxy M 87 was observed at TeV energies with the Cherenkov telescopes of the H.E.S.S. collaboration (High Energy Stereoscopic System). The observations have been performed in the year 2003 during the comissioning phase and in 2004 with the full four telescope setup. The observations were motivated by the measurement of the HEGRA collaboration which reported a 4.7 sigma excess of TeV gamma-rays from the direction of M 87. The results of the H.E.S.S. observations - indicating a possible variability of TeV gamma-ray emission from M 87 (compared to the HEGRA result) - are presented. 
M. Beilicke (1), W. Benbow (2), R. Cornils (1), G. Heinzelmann (1), D.   Horns (3), M. Raue (1), J. Ripken (1), M. Tluczykon...