Separating Isoscalar And Isovector Dipole Excitations In Li-6 And He-6 Using Heavy-Ion Collisions And Nuclear-Coulomb Interference Effects

Nuclear dipole excitation has been used as a probe of nuclear structure. To unveil the structure of various excitation modes proposed up to date, a study of isoscalar (IS) and isovector (IV) dipole excitations has been of particular importance. In this paper, we discuss the possibility of separating the dipole excitation cross sections into the IS and IV contributions using heavy-ion collisions at high-incident energies from 100 to 400 MeV/nucleon. We examine the dipole transitions of Li-6 and He-6 on carbon and lead targets and quantify the nuclear, Coulomb, and their interference contributions. We show that the IS and IV separation can be made in a certain degree of accuracy when appropriate target and incident energies are chosen for each case of Li-6 and He-6. (C) 2021 Elsevier B.V. All rights reserved.