ASTRA Astrophysics and Space Sciences Transactions ASTRA 1810-6536 Copernicus GmbH Göttingen, Germany 10.5194/astra-7-257-2011 Results from the Telescope Array Experiment D. Ikeda<sup>1</sup> for the Telescope Array collaboration<sup>*</sup> 1 2 Institute for Cosmic Ray Research, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8582, Japan <a href="http://www.telescopearray.org" target="_blank">http://www.telescopearray.org</a> 04 07 2011 7 3 257 263 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.astrophys-space-sci-trans.net/7/257/2011/astra-7-257-2011.html The full text article is available as a PDF file from http://www.astrophys-space-sci-trans.net/7/257/2011/astra-7-257-2011.pdf

The Telescope Array experiment is the largest hybrid detector to observe ultra-high energy cosmic rays in the northern hemisphere. The observation started in November 2007 for Fluorescence Detector (FD) and in March 2008 for Surface Detectors (SD). Here we present the preliminary results of energy spectra measured by three different methods, mass composition, photon search and AGN correlation search from the Telescope Array. The energy spectra measured by the Middle-Drum FD station, which is the refurbished detector of the High Resolution Fly's Eye (HiRes) experiment, and hybrid technique with two new FDs and SD were consistent with the result of HiRes. The systematic error of the energies in hybrid measurement is 19%. The SD spectrum showed the suppression above 10<sup>19.75</sup> eV with 3.5σ away from the continuous spectrum. The measured mass composition with stereo technique of new FDs was consistent with pure proton model between 10<sup>18.6</sup> eV to 10<sup>19.3</sup> eV. Photon search resulted in an improved flux limit above 10<sup>19</sup> eV. The result of AGN correlation from TA was consistent with background.

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