Role of Coulomb-nuclear breakup of 6,7Li projectiles with heavy deformed 232Th target

Abstract

The significance of both Coulomb and nuclear couplings and their interference effects in the breakup processes of ^6,7Li with a non-spherical nucleus ²³²Th has been evaluated. The continuum discretized coupled channel (CDCC) calculations are carried out in a nonstandard way, using short-range imaginary potentials for the fragment-target interaction at energies close to the Coulomb barrier. The present calculations employing short-range imaginary potentials exhibit better agreement with the experimental elastic scattering angular distributions than those using standard systematic value ($0.78\times W_{SPP}$) used to describe elastic scattering. Including the excitation of the ²³²Th inelastic shows significant coupling effects on the elastic scattering below the barrier energies compared to higher incident energies. Subsequently, the CDCC framework was used to analyze the nuclear, Coulomb, and total breakup predictions separately. The breakup cross sections for the ⁶Li+²³²Th system are greater than those for the ⁷Li+²³²Th system across various energies. The present study predicts destructive Coulomb-nuclear interference in the breakup processes involving both ⁶Li and ⁷Li projectile nuclei with the deformed ²³²Th target. Additionally, the breakup reaction cross-sections are compared with experimentally measured fusion cross-sections near the barrier energies for both ^6,7Li+²³²Th systems.