α-transfer contribution to 9Be+13C elastic and inelastic scattering

Angular distributions for the 9Be+13C elastic and inelastic scattering have been measured at a 9Be bombarding energy of 50.46 MeV over an angular range from 10 degree to 170 degree c.m. Besides the ground state of 13C, the 3.68 MeV Jπ=3/2- and the 7.55 MeV Jπ=5/2- levels are strongly populated. The enhancement of the backward cross section is clear evidence that the process is dominated by the exchange of an α particle between two identical 9Be cores. The experimental relative integrated cross sections are fairly well reproduced by distorted wave calculations using an α-cluster form factor and the shell-model spectroscopic strengths of Kurath