Angular momentum population in fragmentation reactions

Using a relativistic transport model followed by a statistical sequential binary emission model, the population of metastable high-spin isomeric states are studied in relativistic projectile fragmentation reactions. The initial angular momentum distribution are generated from hole excitations. We find that the angular momentum distribution of the excited prefragments are considerably broadened due to light particle evaporation. The model reproduces the experimentally measured population of relatively low-lying states and underpredicts states with high angular momentum I⩾17ℏI⩾17ℏ. We propose that coupling the spin of the excited and hole states in the prefragment will give a better understanding of the data.