${}_{}{}^{58}{}_{}{}^{}\mathrm{induced}$ one- and two-neutron transfer reactions have been measured on ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ at ${\mathit{E}}_{\mathrm{lab}}$=500 MeV. The transfer probabilities at large internuclear distances measured for the deformed ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ target are compared with similar data on spherical ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. For one-neutron transfer reactions good agreement between experiment and the prediction from the tunneling model is observed in both cases. The transfer probabilities for two-neutron transfer reactions deviate from the semiclassical predictions. The disagreement increases at higher bombarding energies. These deviations can be explained by the influence of diffractive effects which become more important at higher bombarding energies.

• Received 23 October 1992

DOI:https://doi.org/10.1103/PhysRevC.47.2731