TeV/X-ray observations of Mkn 501 during 1997 and 1998

Krawczynski, H.; Aharonian, F. A.; Sambruna, R. M.; Chou, L.; Coppi, P. S.; Urry, C. M.
April 2000
AIP Conference Proceedings;2000, Vol. 510 Issue 1, p323
Academic Journal
The stereoscopic Cherenkov telescope system of HEGRA was used in 1997 and in 1998 to observe the BL Lac object Mkn 501 on a regular basis. After a period of exceptional activity in 1997 of continuous flares and a mean flux roughly one order of magnitude stronger than in the preceding years the source returned in 1998 to a state of moderate flux levels with only very sparse flaring activity. In this paper we summarize the TeV characteristics of Mkn 501 as deduced from the 1997 and 1998 HEGRA observations. Furthermore, we describe a joint HEGRA/RXTE campaign which we organized in June 1998. © 2000 American Institute of Physics.


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