Four-body effects on 9Be + 208Pb scattering and fusion around the Coulomb barrier

TL;DR

This study models 9Be + 208Pb scattering and fusion near the Coulomb barrier using a three-body approach for 9Be and continuum discretization, revealing continuum effects are more significant at lower energies.

Contribution

It introduces a three-body model for 9Be and applies the CDCC method to analyze scattering and fusion, achieving good agreement with experimental data without parameter fitting.

Findings

Continuum effects increase at lower energies.

Good agreement with experimental cross sections.

No parameter fitting was necessary.

Abstract

We investigate the 9Be + 208Pb elastic scattering and fusion at energies around the Coulomb barrier. The $^9$Be nucleus is described in a \alpha + \alpha + n three-body model, using the hyperspherical coordinate method. The scattering with $^{208}$Pb is then studied with the Continuum Discretized Coupled Channel (CDCC) method, where the \alpha + \alpha + n continuum is approximated by a discrete number of pseudostates. Optical potentials for the $\alpha+^{208}$Pb and $n+^{208}$Pb systems are taken from the literature. We present elastic-scattering and fusion cross sections at different energies, and investigate the convergence with respect to the truncation of the \alpha + \alpha + n continuum. A good agreement with experiment is obtained, considering that there is no parameter fitting. We show that continuum effects increase at low energies.