This award will partially support the operation of the Chicago Air Shower Array (CASA), which has been in construction for the last three years under an NSF grant and is located at the site of the Fly's Eye II detector at Dugway Utah. CASA operates is coincidence with a muon array built by the University of Michigan at Dugway. These complimentary arrays, the largest and most sensitive of their kind, will carry out a program of observations in a search for sources of Ultra High Energy gamma radiation (Energy above 1014 eV). The discovery of such source or sources would contribute to the resolution of the decades-old question of the origin of energetic Cosmic Rays.
