Elastic Scattering of the ⁶Li + ²⁷Al system at energies near the Coulomb barrier: From Angular Distributions to Geometric Parameters

¹ Facultad de Ciencias, Universidad Autónoma del Estado de México, Instituto Literario 100, Código Postal 50000, Toluca, México.
² Departamento de Aceleradores y Estudio de Materiales, Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, Código Postal 11801, México, D.F., México.

^* e-mail: jmoralesriv@uaemex.mx

Published online: 1 August 2025

Abstract

In this study, we present the experimental elastic scattering angular distributions for the ²⁷Al(⁶Li, ⁶Li) reaction at energies near the Coulomb barrier: 8.5, 9.0, and 10.0 MeV. The experiment was carried out at the 6 MV Tandem Van de Graaff Accelerator Laboratory of the National Institute for Nuclear Research (ININ) in Mexico. Theoretical calculations were performed using the FRESCO code, and its search version SFRESCO, considering the Woods-Saxon (W-S) form factor and the São Paulo Potential (SPP) to model angular distributions. Additionally, an approach based on the Extended Optical Model was employed to extract optical model parameters, revealing systematic trends in the real and imaginary components of the potential. These trends indicate an increase in absorption effects at higher energies, consistent with previous studies. The results contribute to a better understanding of the Breakup Threshold Anomaly (BTA), a phenomenon associated to weakly bound nuclei. As a future direction, we plan to perform a more detailed analysis of the BTA and its influence on nuclear absorption, and we will extend this approach to other energy regimes.