The Search for Anisotropy in the Arrival Directions of Ultra-High Energy   Cosmic Rays Observed by the High Resolution Fly's Eye Detector in Monocular   Mode
  The High Resolution Fly's Eye HiRes-I detector has now been in operation in monocular mode for over six years. During that time span, HiRes-I has accumulated a larger exposure to Ultra-High Energy Cosmic Rays (UHECRs) above 10^19 eV than any other experiment built to date. This presents an unprecedented opportunity to search for anisotropy in the arrival directions of UHECRs. We present results of a search for dipole distributions oriented towards major astrophysical landmarks and a search for small-scale clustering. We conclude that the HiRes-I data set is, in fact, consistent with an isotropic source model. 
Benjamin T. Stokes (for the High Resolution Fly's Eye Collaboration,   HiRes)