This award will support Professor Thomas Gaisser and Todor Stanev of the Bartol Research Institute at the University of Delaware in a research collaboration with Professor Giulio Auriemma of the Universita "La Sapienza" in Rome, Italy. The researchers propose to investigate the interpretation and theoretical implications of novel experiments being performed in several deep underground laboratories around the world that detect remnants of ultra-high energy natural radiation from outer space. They will carry out computer simulations and other calculations necessary to interpret measurements of coincident multiple muons, of neutrino-induced upward muons, and of correlations between surface and underground observations. They will also study the implications of the measurements for cosmic ray physics, for neutrino astronomy and for properties of elementary particles. The work proposed here will be coordinated with the new experiments that are coming into operation now in association with the Gran Sasso Laboratory at L'Acquila in Italy. This support will serve to increase significantly ongoing cooperative research in particle-astrophysics. The researchers will take advantage of the operation of major new underground detectors at the Gran Sasso Laboratory such as MACRO (Monopole, Astrophysics and Cosmic Ray Observatory) as well as other underground experiments in the planning stage in Italy.
