On ternary fission induced by high-energy protons

Uranium was irradiated with high-energy protons: 600 MeV. 2.9 GeV, 12.3 GeV and 21.8 GeV. Through the use of nuclear emulsions as detectors, three-prong events with cross-sections of (1.2±0.1) mb, (2.2±0.1) mb, (4.8±0.8) mb and (6.5±1.2) mb, respectively, were found, along with the usual fission tracks. Our results show that as well as a true ternary fission process, a variety of other phenomena exist which can produce three-prong events and must be taken carefully into account.