An One Dimensional Adiabatic Model for Fusion Involving Loosely Bound and Halo Nuclei with Heavy Targets

Abstract

An one dimensional adiabatic model has been proposed for fusion of loosely bound and halo light nuclei with various heavy targets. It is shown that fusion cross sections at near and sub-barrier energies can be explained using a simple WKB tunneling through an adiabatic barrier without invoking breakup coupling explicitly. The model has been applied successfully to explain fusion cross sections for several systems including recently measured $^{6}Li+^{198}Pt$ system (Phy. Rev. Lett. 103, 232702, 2009) where data exists well above and below the barrier and $^{8}He+^{197}Au$ system (Phy. Rev. Lett. 103, 232701, 2009) where $^{8}He$ is highly neutron rich. Interestingly, the fusion of stable $^{4}He+^{197}Au$ system can not be explained on the basis of this adiabatic model as it requires normal tunneling through the sudden barrier. The requirement of adiabatic potential for the loosely bound and halo nuclei is linked to the fact that for such systems neutron flow leading to neck formation is initiated at a larger distance which modifies the sudden potential.