Sub-barrier capture with quantum diffusion approach

TL;DR

This paper uses the quantum diffusion approach to analyze sub-barrier nuclear capture, revealing an unexpected enhancement of capture cross sections at energies far below the Coulomb barrier and emphasizing the role of quasifission.

Contribution

It introduces the quantum diffusion approach to study sub-barrier capture, highlighting the change in interaction regime and the significance of quasifission in certain nuclear reactions.

Findings

Enhanced capture cross sections at deep sub-barrier energies.

Change in nuclear interaction regime at low energies.

Quasifission plays a crucial role in actinide and medium-heavy nuclei reactions.

Abstract

With the quantum diffusion approach the behavior of capture cross sections and mean-square angular momenta of captured systems are revealed in the reactions with deformed and spherical nuclei at sub-barrier energies. With decreasing bombarding energy under the barrier the external turning point of the nucleus-nucleus potential leaves the region of short-range nuclear interaction and action of friction. Because of this change of the regime of interaction, an unexpected enhancement of the capture cross section is found at bombarding energies far below the Coulomb barrier. This effect is shown its worth in the dependence of mean-square angular momentum on the bombarding energy. From the comparison of calculated capture cross sections and experimental capture or fusion cross sections the importance of quasifission near the entrance channel is demonstrated for the actinidebased reactions and reactions with medium-heavy nuclei at extreme sub-barrier energies.