Simultaneous study of scattering and fusion hindrance near Coulomb barrier in $F+Pb$ systems

TL;DR

This study uses a phenomenological optical potential to analyze scattering and fusion hindrance near the Coulomb barrier in fluorine-lead systems, revealing fusion hindrance in isotopic variants of fluorine.

Contribution

It introduces a flexible optical potential model to simultaneously study scattering and fusion hindrance in F+Pb systems, including isotopic variations.

Findings

Fusion occurs unimpeded in $^{19}F+^{208}Pb$ below the Coulomb barrier.

Fusion is hindered in isotopic fluorine projectiles.

Theoretical results agree with experimental data across multiple groups.

Abstract

A phenomenological optical potential is used to study the elastic angular distributions for the system $^{19}F+^{208}Pb$ close to the Coulomb barrier. This potential is constructed by taking into account the flexible potential developed by Ginocchio. The fluctuations in the real and imaginary parts of the optical model potential follow the trends of the threshold anomaly. The set of optical potential parameters needed to analyze the fusion cross sections of the same system are obtained through analysis of the scattering cross sections. Theoretical fusion cross-sections and results from four different experimental groups well agree for a range of energies. Several Fluorine (F) isotopes are used as projectiles in this study of fusion cross-sections by slightly altering the radial parameter. It was found that the fusion process occurs unfettered in the $^{19}F +^{208}Pb$ system below the Coulomb barrier but is seriously hindered in the case of its isotopic projectiles.