Vaporization and Multifragmentation in 1.2 GeV Antiproton induced Reactions

With energetic antiproton-light-nucleus interactions it is possible to reach excitation energies exceeding nuclear binding energy. For 1.2 GeV +Cu we observe the onset of vaporization at about 8 MeV/nueleon, but even at 15 MeV/nucleon the probability of vaporization is smaller than 15%. The threshold excitation energy for multifragmentation processes defined as the detection of at least 3 intermediate mass fragments is observed at about 4 MeV/nucleon for 1.2 GeV + Cu and Ag. The probability of multifragmentation is small and even at excitation energy above the total binding energy not larger than 5% and 20% of the corresponding inclusive cross sections.