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An Upper Limit on the Infrared Background Density from HEGRA data on Mkn501

B. Funk·N. Magnussen·H. Meyer·W. Rhode·S. Westerhoff·B. Wiebel-Sooth
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Abstract

The energy spectrum of Mkn501 in the TeV energy regime, as measured by the HEGRA (High Energy Gamma Ray Astronomy) Cerenkov telescopes during its low state in 1995/96 and during a fraction of the 1997 outburst in the TeV energy regime, is shown to place stringent upper limits on the still unknown infrared photon density in the energy region between 3 x 10**(-3) and 3 xt 10**(-1) eV. Assuming two different shapes for the unknown infrared photon spectrum in this energy range we calculate upper limits on the infrared photon density on the basis of the power-law fit obtained for the observed spectrum up to the maximum energy.

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B. Funk, N. Magnussen, H. Meyer, W. Rhode, S. Westerhoff, B. Wiebel-Sooth. 1998-02-24. An Upper Limit on the Infrared Background Density from HEGRA data on Mkn501. https://doi.org/10.1016/s0927-6505(98)00009-7

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