Non-local effects on the heavy-ion fusion at sub-barrier energies

TL;DR

This paper examines the impact of Pauli non-locality on sub-barrier heavy-ion fusion reactions, specifically assessing the adequacy of the São Paulo potential in modeling these effects.

Contribution

It evaluates the validity of the São Paulo potential, derived from semi-classical approximations, for describing non-local effects in heavy-ion fusion at sub-barrier energies.

Findings

Non-locality has a minor effect on fusion at sub-barrier energies.

The São Paulo potential is adequate for modeling these reactions.

The approximation used in deriving the potential is justified for charged particle tunneling.

Abstract

We investigate the effect of Pauli non-locality in the heavy-ion optical potential on sub-barrier fusion reactions. The S\~{a}o Paulo potential, which takes into account the Pauli non-locality and has been widely used in analyzing elastic scattering, has also recently been applied to heavy-ion fusion. However, the approximation employed in deriving the S\~{a}o Paulo potential, based on the Perey-Buck semi-classical treatment of neutron induced reactions, must be assessed for charged particles tunneling through a barrier. It is the purpose of this note to look into this question. We consider the widely studied system $^{16}$O + $^{208}$Pb at energies that span the barrier region from 10 MeV below to 10 MeV above. It seems that the non-locality plays a minor role. We find the S\~{a}o Paulo potential to be quite adequate throughout the region.