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Very high energy gamma rays from Markarian 501

R. J. Protheroe·C. L. Bhat·P. Fleury·E. Lorenz·M. Teshima·T. C. Weekes
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Abstract

During remarkable flaring activity in 1997 Markarian 501 was the brightest source in the sky at TeV energies, outshining the Crab Nebula by a factor of up to 10. Periods of flaring activity each lasting a few days were observed simultaneously by several gamma ray telescopes. Contemporaneous multiwavelength observations in April 1997 show that a substantial fraction of the total AGN power is at TeV energies indicating that high energy processes dominate the energetics of this object. Rapid variability, on time scales of less than a day, and a flat spectrum extending up to at least 10 TeV characterize this object. Results of 1997 observations by 6 telescopes are summarized and some of the implications of these results are discussed.

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R. J. Protheroe, C. L. Bhat, P. Fleury, E. Lorenz, M. Teshima, T. C. Weekes. 1997-10-12. Very high energy gamma rays from Markarian 501. https://arxiv.org/abs/astro-ph/9710118

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