Observation of the Crab Nebula Gamma-Ray Emission Above 220 Gev by the Cat Cherenkov Imaging Telescope

A. Barrau; R. Bazer-Bachi; H. Cabot; L. M. Chounet; G. Debiais; B. Degrange; J. P. Dezalay; A. Djannati-Atai; D. Dumora; P. Espigat; B. Fabre; P. Fleury; G. Fontaine; R. George; C. Ghesquiere; P. Goret; C. Gouiffes; I. A. Grenier; L. Iacoucci; S. Le Bohec; I. Mallet; C. Meynadier; F. Munz; T. A. Palfrey; E. Pare; Y. Pons; M. Punch; J. Quebert; K. Ragan; C. Renault; M. Rivoal; L. Rob; P. Schovanek; D. Smith; J. P. Tavernet; J. Vrana

arXiv · astro-ph/9705248

Observation of the Crab Nebula Gamma-Ray Emission Above 220 Gev by the Cat Cherenkov Imaging Telescope

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Abstract

The CAT imaging telescope, recently built on the site of the former solar plant Themis (French Pyrenees), observed gamma-rays from the Crab nebula from October 1996 to March 1997. This steady source, often considered as the standard candle of very-high-energy gamma-ray astronomy, is used as a test-beam to probe the performances of the new telescope, particularly its energy threshold (220 GeV at 20 degrees zenith angle) and the stability of its response. Due to the fine-grain camera, an accurate analysis of the longitudinal profiles of shower images is performed, yielding the source position in two dimensions for each individual shower.

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A. Barrau, R. Bazer-Bachi, H. Cabot, L. M. Chounet, G. Debiais, B. Degrange, J. P. Dezalay, A. Djannati-Atai, D. Dumora, P. Espigat, B. Fabre, P. Fleury, G. Fontaine, R. George, C. Ghesquiere, P. Goret, C. Gouiffes, I. A. Grenier, L. Iacoucci, S. Le Bohec, I. Mallet, C. Meynadier, F. Munz, T. A. Palfrey, E. Pare, Y. Pons, M. Punch, J. Quebert, K. Ragan, C. Renault, M. Rivoal, L. Rob, P. Schovanek, D. Smith, J. P. Tavernet, J. Vrana. 1997-05-30. Observation of the Crab Nebula Gamma-Ray Emission Above 220 Gev by the Cat Cherenkov Imaging Telescope. https://arxiv.org/abs/astro-ph/9705248

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