Anomalies in α-scattering and (3He, α) reactions on 40, 41Ca and the effect of cluster exchange

Abstract

Elastic α-scattering angular distributions have been measured on 40, 41Ca at 19, 24.1 and 26.5 MeV. Both isotopes exhibit anomalous backward scattering cross sections at all three energies. Anomalies are also found in the forward angle cross sections for 40, 41Ca(3He, α) reactions, measured for six final states at incident 3He energies varied in steps of 1 MeV between 16 MeV and 27 MeV. The appearance of these anomalously high cross sections can be qualitatively understood to arise from cluster substitution and exchange mechanisms acting both in elastic α-scattering and in the (3He, α) reaction. © 1975.