Search for Large-Scale Anisotropy of Ultrahigh Energy Cosmic Rays with HiRes Stereo Data

We report on a search for correlations between local large-scale structure and arrival directions of ultrahigh energy cosmic rays, detected by the High Resolution Fly's Eye (HiRes) experiment operating in stereoscopic mode. HiRes has observed cosmic rays with energies up to just over 100 EeV. The highest energy events have a relatively nearby horizon, and one expects that they should point back to their sources to a few-degree accuracy, or at least toward local large-scale structure. HiRes currently has the largest exposure of any experiment in the northern hemisphere. The experiment and search methods will be described and results will be presented.