Intrinsic anisotropy of the UHECR from the Pierre Auger Observatory

Using a differential two-point correlation method, we examine the distribution of arrival directions of the highest energy cosmic rays detected with the Pierre Auger Observatory. We compare this distribution against a hypothesis of isotropy. The number of pairs of events at a small angular scale is consistent with an isotropic distribution only 3 percent of the time. We also study the number of pairs at a small angular scale as a function of the energy of the cosmic rays. Data show an anisotropic distribution only at energies above 57 EeV.