Hybrid analysis for the Telescope Array

Abstract

The Telescope Array (TA) experiment is the largest Ultra-High Energy Cosmic Ray (UHECR) hybrid detector which consists of three stations of Fluorescence Detectors (FDs) and 507 Surface Detectors (SDs). The coincidence events which observed both by FD and SD is referred as hybrid event. The geometry and energy of each extensive air shower observed by hybrid mode are reconstructed with much more accurate resolution than monocular reconstruction alone. The hybrid event candidates were searched for by comparison of the trigger times between FD and SD in the good weather days from May 2008 to September 2010. By this search, we found 1306 hybrid events for BR, 1051 events for LR and 905 events for MD. In this paper, the performance of the hybrid technique and the energy spectra measured by using hybrid events are presented.