Role of Neutron Transfer in Sub-Barrier Fusion

Abstract

Fusion excitation function of ${}^{35}$Cl + ${}^{130}$Te system is measured in the energy range around the Coulomb barrier and analyzed in the framework of the coupled-channels approach. The role of projectile deformation, nuclear structure, and the couplings of inelastic excitations and positive Q$-$value neutron transfer channels in sub-barrier fusion are investigated through the comparison of reduced fusion excitation functions of ${}^{35,37}$Cl +${}^{130}$Te systems. The reduced fusion excitation function of ${}^{35}$Cl + ${}^{130}$Te system shows substantial enhancement over ${}^{37}$Cl + ${}^{130}$Te system in sub-barrier energy region which is attributed to the presence of positive Q-value neutron transfer channels in ${}^{35}$Cl + ${}^{130}$Te system. Findings of this work strongly suggest the importance of +2$n$ - transfer coupling in sub-barrier fusion apart from the simple inclusion of inelastic excitations of interacting partners, and are in stark contrast with the results presented by Kohley \textit{et al.}, [Phys. Rev. Lett. 107, 202701 (2011)].

6 pages, 4 figures