The Cosmic Ray Energy Spectrum Observed with the Surface Detector of the Telescope Array Experiment
Abstract
The Telescope Array (TA) collaboration has measured the energy spectrum of ultra-high energy cosmic rays with primary energies above 1.6 x 10^(18) eV. This measurement is based upon four years of observation by the surface detector component of TA. The spectrum shows a dip at an energy of 4.6 x 10^(18) eV and a steepening at 5.4 x 10^(19) eV which is consistent with the expectation from the GZK cutoff. We present the results of a technique, new to the analysis of ultra-high energy cosmic ray surface detector data, that involves generating a complete simulation of ultra-high energy cosmic rays striking the TA surface detector. The procedure starts with shower simulations using the CORSIKA Monte Carlo program where we have solved the problems caused by use of the "thinning" approximation. This simulation method allows us to make an accurate calculation of the acceptance of the detector for the energies concerned.
Keywords
Cite
@article{arxiv.1205.5067,
title = {The Cosmic Ray Energy Spectrum Observed with the Surface Detector of the Telescope Array Experiment},
author = {T. Abu-Zayyad and R. Aida and M. Allen and R. Anderson and R. Azuma and E. Barcikowski and J. W. Belz and D. R. Bergman and S. A. Blake and R. Cady and B. G. Cheon and J. Chiba and M. Chikawa and E. J. Cho and W. R. Cho and H. Fujii and T. Fujii and T. Fukuda and M. Fukushima and W. Hanlon and K. Hayashi and Y. Hayashi and N. Hayashida and K. Hibino and K. Hiyama and K. Honda and T. Iguchi and D. Ikeda and K. Ikuta and N. Inoue and T. Ishii and R. Ishimori and D. Ivanov and S. Iwamoto and C. C. H. Jui and K. Kadota and F. Kakimoto and O. Kalashev and T. Kanbe and K. Kasahara and H. Kawai and S. Kawakami and S. Kawana and E. Kido and H. B. Kim and H. K. Kim and J. H. Kim and J. H. Kim and K. Kitamoto and S. Kitamura and Y. Kitamura and K. Kobayashi and Y. Kobayashi and Y. Kondo and K. Kuramoto and V. Kuzmin and Y. J. Kwon and J. Lan and S. I. Lim and S. Machida and K. Martens and T. Matsuda and T. Matsuura and T. Matsuyama and J. N. Matthews and M. Minamino and K. Miyata and Y. Murano and I. Myers and K. Nagasawa and S. Nagataki and T. Nakamura and S. W. Nam and T. Nonaka and S. Ogio and M. Ohnishi and H. Ohoka and K. Oki and D. Oku and T. Okuda and A. Oshima and S. Ozawa and I. H. Park and M. S. Pshirkov and D. C. Rodriguez and S. Y. Roh and G. Rubtsov and D. Ryu and H. Sagawa and N. Sakurai and A. L. Sampson and L. M. Scott and P. D. Shah and F. Shibata and T. Shibata and H. Shimodaira and B. K. Shin and J. I. Shin and T. Shirahama and J. D. Smith and P. Sokolsky and B. T. Stokes and S. R. Stratton and T. A. Stroman and S. Suzuki and Y. Takahashi and M. Takeda and A. Taketa and M. Takita and Y. Tameda and H. Tanaka and K. Tanaka and M. Tanaka and S. B. Thomas and G. B. Thomson and P. Tinyakov and I. Tkachev and H. Tokuno and T. Tomida and S. Troitsky and Y. Tsunesada and K. Tsutsumi and Y. Tsuyuguchi and Y. Uchihori and S. Udo and H. Ukai and G. Vasiloff and Y. Wada and T. Wong and M. Wood and Y. Yamakawa and R. Yamane and H. Yamaoka and K. Yamazaki and J. Yang and Y. Yoneda and S. Yoshida and H. Yoshii and X. Zhou and R. Zollinger and Z. Zundel},
journal= {arXiv preprint arXiv:1205.5067},
year = {2013}
}
Comments
Accepted for publication by Astrophysical Journal Letters