Measurement of anisotropy of ultra-high energy cosmic rays by the Telescope Array.

We study anisotropy of ultra-high energy cosmic ray (UHECR) events collected by the Telescope Array detector in the first 2 years of operation. We find that the self-correlation function of UHECR at energies larger 10 and 40 EeV shows no significant small-scale clustering. The events with energy E>57 EeV do not significantly correlate with the positions of the nearby active galactic nuclei (AGN): of observed 15 events 6 are found within 3.7° from an AGN, while 3.6 are expected for a random distribution (16% chance probability). We also check the event sets with energies E>40 EeV and E>57 EeV for correlations with the large scale structure (LSS) of the Universe. We find that both data sets are compatible with the LSS model at the 95% confidence level. [ABSTRACT FROM AUTHOR]