ar X iv : a st ro - p h / 99 04 40 5 v 1 2 9 A pr 1 99 9 Observations of TeV gamma rays from Markarian 501 at large zenith angles
نویسندگان
چکیده
TeV gamma rays from the blazar Markarian 501 have been detected with the University of Durham Mark 6 atmospherič Cerenkov telescope using the imaging technique at large zenith angles. Observations were made at zenith angles in the range 70 • − 73 • during 1997 July and August when Markarian 501 was undergoing a prolonged and strong flare.
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