The arrival direction distribution of Extremely High En- ergy cosmic rays observed by AGASA

Study of the arrival direction distribution plays a key role in finding sources of the Extremely High Energy Cosmic Rays (EHECR). Greisen-Zatsepin-Kuz’min (GZK) mechanism [1,2] limits the propagation of EHE cosmic rays significantly and only nearby sources can contribute to the local EHECR flux[3-6]. Furthermore EHECRs travel intergalactic spaces almost linearly. Hence, we expect they can be traced back to their sources. Here we report a small-sacle anisotropy of the arrival direction distribution of EHECRs observed by AGASA above 10 19 eV . This result strongly suggests the existence of point sources of EHECRs.