Multinucleon transfer in the Cd116(Ne20,O20)Sn116 double charge exchange reaction at 306 MeV incident energy

Abstract

In heavy-ion collisions at energies above the Coulomb barrier, the multiple nucleon transfer mechanism feeding double charge exchange (DCE) reactions can compete with the meson-induced DCE process once, in both cases, the same final partition is achieved. While the former is a mean field driven process, the latter is generated by second-order isovector components of the nucleon-nucleon interaction. It is particularly interesting to isolate the meson-induced DCE from measured cross sections since their matrix elements can be linked to those controlling the expected double $\ensuremath{\beta}$ decay rates. However, one needs first to isolate the meson-induced DCE contribution, which in turn means that careful scrutiny of the DCE flux from the multinucleon transfer is mandatory. This work presents theoretical results for all the multinucleon transfer routes feeding the $^{116}\mathrm{Cd}(^{20}\mathrm{Ne},^{20}\mathrm{O})^{116}\mathrm{Sn}$ reaction at 306 MeV incident energy. The calculated cross sections are obtained considering the distorted wave Born approximation and coupled channel Born approximation, where the role of the couplings with inelastic states in the initial partition is discussed. Moreover, the spectroscopic amplitudes for the projectile and target overlaps are extracted by considering a large-scale shell-model calculation.