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H. Krawczynski (Max-Planck-Institut f. Kernphysik, now at Yale University, Dept. of Astronomy), F. Aharonian (Max-Planck-Institut f. Kernphysik), P.S. Coppi (Yale University, Dept. of Astronomy), R. Sambruna (George Mason University, Dept. of Physics and Astronomy), HEGRA Collaboration
The HEGRA collaboration operates a system of 5 Imaging Atmospheric Cherenkov Telescopes for gamma-ray astronomy in the energy range above 500 GeV. Based on the method of stereoscopic air shower observations the system achieves an energy flux sensitivity at 1 TeV of approximately 10-11 ergs/cm2 sec for 1 hour of observation time as well as an angular and energy resolution per individual photon of 0.1 degree and <20%, respectively. In this contribution we present TeV gamma-ray (HEGRA) and X-ray (RXTE) data taken during several intense multiwavelength campaigns on the BL Lac objects Mkn 501 and Mkn 421 during the years of 1997 until 2000. The diurnal observations with detailed information about flux and spectrum at TeV gamma-ray and X-ray energies show that the TeV gamma-ray and X-ray emission strengths are tightly correlated. Furthermore, we present fits of a time dependent Synchrotron Self-Compton model to the multiwavelength data. The wealth of information encoded in the temporal evolution of absolute fluxes and spectral hardnesses at TeV gamma-ray and X-ray energies makes it possible to tightly constrain parameters describing the emission region and to elucidate which of these parameters changed during individual TeV gamma-ray/X-ray flares. The detailed modeling of the non-thermal emission allows us to infer information about the intensity of the Diffuse Extragalactic Background Radiation in the 1-50 micron wavelength range which modifies the TeV energy spectra due to pair-production processes.
The author(s) of this abstract have provided an email address for comments about the abstract: Henric.Krawczynski@mpi-hd.mpg.de