SPALLATION CROSS-SECTIONS IN THE SYSTEM NB-93 + HE-4

Excitation functions were measured for six radioactive products formed in the reaction between 93Nb and 4He ions in the energy range 15-72 MeV. Agreement between experimental values and theoretical calculations was satisfactory only if allowance was made for pre-equilibrium (PE) nucleon emission. The compound nucleus (CN) model alone fails to account for the high energy tail in many of the excitation functions. The calculations do not give a particularly good fit for the (α, 2p) and (α, α′n) reactions which are very sensitive to parameters describing compound nucleus decay and the initial interaction respectively. © 1979.