Dynamical nucleus-nucleus potential at short distances

TL;DR

This paper investigates the dynamical nucleus-nucleus potentials at short distances for various fusion reactions using the ImQMD model, revealing energy-dependent behaviors and comparisons with experimental and other theoretical results.

Contribution

It introduces an improved quantum molecular dynamics model combined with the extended Thomas-Fermi approximation to study fusion potentials at short distances.

Findings

Fusion barrier for 40Ca+40Ca matches experimental data.

Fusion pockets are shallow or nearly vanish in heavy symmetric systems.

Potential at short distances exceeds the adiabatic potential in heavy systems.

Abstract

The dynamical nucleus-nucleus potentials for fusion reactions 40Ca+40Ca, 48Ca+208Pb and 126Sn+130Te are studied with the improved quantum molecular dynamics (ImQMD) model together with the extended Thomas-Fermi approximation for the kinetic energies of nuclei. The obtained fusion barrier for 40Ca+40Ca is in good agreement with the extracted fusion barrier from the measured fusion excitation function, and the depth of the fusion pockets are close to the results of time-dependent Hartree-Fock calculations. The energy dependence of fusion barrier is also investigated. For heavy fusion system, the fusion pocket becomes shallow and almost disappears for symmetric systems and the obtained potential at short distances is higher than the adiabatic potential.