Alpha Production by 28.5-BeV Proton Incident on Beryllium Oxide

A sizable number of $\alpha$ particles were detected at 18.8° in $p$-BeO collisions at 28.5 BeV. The alpha-to-deuteron ratio is found to be of the order of 1% for secondary momenta below 1000 MeV/c per nucleon. Possibilities of obtaining secondary alpha beams at high-energy accelerators for various experiments, in particular those relevant to the study of the origin and propagation of cosmic rays, are discussed.