Spallation cross sections in the system 93Nb + 4He

Excitation functions were measured for six radioactive products formed in the reaction between 93Nb and 4He ions in the energy range 15 to 72 MeV. Agreement between experimental values and theoretical calculations was satisfactory only if allowance was made for pre-equilibrium nucleon emission. The compound nucleus 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. (author)