Observation of Spectrum of TeV Gamma Rays up to 60 TeV from the Crab at the Large Zenith Angles

K. Sakurazawa; T. Tanimori; S. A. Dazeley; P. G. Edwards; T. Hara; S. Kamei; T. Kifune; R. Kita; T. Konishi; A. Masaike; Y. Matsubara; Y. Matsuoka; Y. Mizumoto; M. Mori; H. Muraishi; Y. Muraki; T. Naito; K. Nishijima; S. Ogio; J. R. Patterson; M. D. Roberts; G. P. Rowell; T. Sako; R. Susukita; A. Suzuki; R. Suzuki; T. Tamura; G. J. Thornton; S. Yanagita; T. Yoshida; T. Yoshikoshi

arXiv · astro-ph/9707002

Observation of Spectrum of TeV Gamma Rays up to 60 TeV from the Crab at the Large Zenith Angles

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Abstract

The CANGAROO experiment has observed gamma-ray above 7TeV from the Crab pulsar/nebula at large zenith angle in Woomera, South Australia. We report the CANGAROO data taken in 1992, 1993 and 1995, from which it appears that the energy spectrum extends at least up to 50 TeV. The observed integral spectrum is (8.4+-1.0) x 10^{-13}(E/7 TeV)^(-1.53+-0.15)cm^{-2}s^{-1} between 7 TeV and 50 TeV. In November 1996, the 3.8m mirror was recoated in Australia, and its reflectivity was improved to be about 90% as twice as before. Due to this recoating, the threshold energy of ~4 TeV for gamma rays has been attained in the observation of the Crab at large zenith angle. Here we also report the preliminary result taken in 1996.

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K. Sakurazawa, T. Tanimori, S. A. Dazeley, P. G. Edwards, T. Hara, S. Kamei, T. Kifune, R. Kita, T. Konishi, A. Masaike, Y. Matsubara, Y. Matsuoka, Y. Mizumoto, M. Mori, H. Muraishi, Y. Muraki, T. Naito, K. Nishijima, S. Ogio, J. R. Patterson, M. D. Roberts, G. P. Rowell, T. Sako, R. Susukita, A. Suzuki, R. Suzuki, T. Tamura, G. J. Thornton, S. Yanagita, T. Yoshida, T. Yoshikoshi. 1997-07-01. Observation of Spectrum of TeV Gamma Rays up to 60 TeV from the Crab at the Large Zenith Angles. https://arxiv.org/abs/astro-ph/9707002

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