Fusion cross sections for [formula omitted] and [formula omitted] reactions at low energies

Abstract

The partial cross sections for the 7Li + 11B and 9Be + 9Be reactions below and above the Coulomb barrier energy have been determined from the cross sections of the characteristic γ-rays of the residual nuclei and using the branching factor σ γ σ ch obtained from the statistical model calculations. The fusion cross sections obtained from the sum of these partial cross sections are found to be equal to the total reaction cross sections upto an energy well above the Coulomb barrier energy for the 9Be + 9Be reaction. For the 7Li + 11B reaction, however, the fusion cross sections are found to be less than the total reaction cross sections at energies not much above the Coulomb barrier. The maximum fusion cross sections for the 7Li + 11B and 9Be + 9Be reactions are found to be ∼66% and ∼81% of the total reaction cross sections at E c.m. = 2 B c (where B c is the Coulomb barrier energy), respectively.