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arXiv · 0907.0832

Detection of the crab pulsar with MAGIC

M. Lopez·N. Otte·M. Rissi·T. Schweizer·M. Shayduk·S. Klepser
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Abstract

The MAGIC telescope has detected for the first time pulsed gamma-rays from the Crab pulsar in the VHE domain. The observations were performed with a newly developed trigger system that allows us to lower the energy threshold of the telescope from 55 GeV to 25 GeV. We present a comparison of light curves measured by our experiment with the one measured by space detectors. A strong energy dependent decrease of the first peak with respect to the second peak P1/P2 could be observed. Finally, fitting our measured data and previous measurements from EGRET we determine a turnover of the energy spectrum at 17.7 +- 2.8 (stat.) +- 5.0 (syst.) GeV, assuming an exponential cutoff. This rules out the scenario in which the gamma rays are produced in vicinity of the polar caps of the neutron star.

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M. Lopez, N. Otte, M. Rissi, T. Schweizer, M. Shayduk, S. Klepser. 2009-07-05. Detection of the crab pulsar with MAGIC. https://arxiv.org/abs/0907.0832

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