Oblate-prolate deformation effect in capture reactions at sub-barrier energies

The role of prolate and oblate deformations of colliding nuclei in the sub-barrier capture process is studied within the quantum-diffusion approach. A comparison of the calculated and measured capture cross sections in the reactions ¹⁶O,⁴⁸Ca+¹⁵⁴Sm and ⁷⁴Ge+⁷⁴Ge show that transitions during the capture process occur from the potential minimum with an oblate deformation of the ground state to the minimum with a prolate deformation of the nuclei ¹⁵⁴Sm and ⁷⁴Ge. These transitions crucially influence the sub-barrier capture. The capture cross sections and mean-angular momenta are predicted for the reactions of ³⁶S+¹⁷⁰Er,¹⁷⁴Yb.