Development of an atmospheric Cherenkov imaging camera for theCANGAROO-III experiment

S. Kabuki, K. Tsuchiya, K. Okumura, R. Enomoto,.,T. Uchida, H. Tsunoo, Shin. Hayashi, Sei. Hayashi, F. Kajino, A. Maeshiro, I. Tada, C. Itoh, A. Asahara, G.V. Bicknell, R.W. Clay, P.G. Edwards, S. Gunji, S. Hara, T. Hara, T. Hattori, H. Katagiri, A. Kawachi, T. Kifune, H. Kubo, J. Kushida, Y. Matsubara, Y. Mizumoto, M. Mori, H. Moro, H. Muraishi, Y. Muraki, T. Naito, T. Nakase, D. Nishida, K. Nishijima, M. Ohishi, J.R. Patterson, R.J. Protheroe, K. Sakurazawa, D.L. Swaby, T. Tanimori, F. Tokanai, A.Watanabe, S.Watanabe, S. Yanagita, T. Yoshida, T. Yoshikoshi
*) enomoto@icrr.u-tokyo.ac.jp

A Cherenkov imaging camera for the CANGAROO-III experiment has been developed for observations of gamma-ray induced air-showers at energies from 10¹¹ to 10¹⁴ eV. The camera consists of 427 pixels, arranged in a hexagonal shape at 0.17 intervals, each of which is a 3/4-inch diameter photomultiplier module with a Winston-coneshaped light guide. The camera was designed to have a large dynamic range of signal linearity, a wider eld of view, and an improvement in photon collection eciency compared with the CANGAROO-II camera. The camera, and a number of the calibration experiments made to test its performance, are described in detail in this paper.