Near and sub-barrier reactions of ⁸B

¹ Physics Department, University of Notre Dame, Notre Dame, Indiana, 46556-5670, USA
² Departamento de Aceleradores, Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, Código Postal 11801, México, Distrito Federal, México
³ Instituto de Fisica, Universidade de São Paulo, Rua do Matão Nr. 1371, 05508-900, São Paulo, SP, Brazil

^* e-mail: jkolata@nd.edu
^** e-mail: eli.aguilera@inin.gob.mx
^*** e-mail: valdirg@if.usp.br

Published online: 22 November 2017

Abstract

Four classes of measurements that are important for achieving a complete understanding of the reactions of exotic nuclei are identified and classified according to their degree of difficulty. Previously reported data for near- and sub-barrier fusion of ⁸B+⁵⁸Ni are critically reviewed. The influence of breakup protons on the evaporation proton measurements for this system is shown to be small at all energies except for the lowest one measured, and corrections are made for this process. Model dependencies in the deduced fusion cross sections are assessed using three different evaporation codes. Data sets for targets of ⁵⁸Ni and ²⁸Si are shown to be consistent with each other, and with fusion enhancement up to energies that are greater than the Coulomb barrier V_b (E_c.m. ≲ V_b + 1.5×ћω). An important difference with the behavior of neutron-halo systems is thereby confirmed. Possible fusion suppression beyond this energy is suggested by the ²⁸Si data. A proposal to measure the ⁸B+⁴⁰Ar fusion cross section using an active-target time projection chamber is discussed.