Evidence for a QPO structure in the TeV and X-ray light curve during the 1997 high state Gamma emission of Mkn 501

Kranich, D.; De Jager, O. C.; Kestel, M.; Lorenz, E.; Collaboration, the HEGRA

Evidence for a QPO structure in the TeV and X-ray light curve during the 1997 high state Gamma emission of Mkn 501

Authors

Collaboration, the HEGRA

Description

The BL Lac Object Mkn 501 was in a state of high activity in the TeV range in 1997. During this time Mkn 501 was observed by all Cherenkov-Telescopes of the HEGRA-Collaboration. Part of the data were also taken during moonshine thus providing a nearly continuous coverage for this object in the TeV-range. We have carried out a QPO analysis and found evidence for a 23 day periodicity. We applied the same analysis on the 'data by dwell' x-ray lightcurve from the RXTE/ASM database and found also evidence for the 23 day periodicity. The combined probability was P = 2.8 *10^-4.
4 Pages, 7 Figures; to appear in the proceedings of the 26th ICRC, Salt Lake City, August 1999