The K-shell ionisation of90Th by protons and alpha particles

Abstract

The cross sections have been measured for K-shell ionisation of 90Th by 1.2-6.0 MeV protons and 2.5-16 MeV alpha particles. The results are derived from comparisons with well known Coulomb excitation cross sections for nuclear rotational transitions. The measured cross sections for protons are in good agreement with the predictions of both the SCA and PWBA models provided both models are supplemented by the same Coulomb deflection, binding and relativistic corrections. The cross sections measured for alpha particles are on the average 30% higher than predicted by the two models mentioned above.