Measurement of Li+Sn fusion excitation functions around the Coulomb barrier using an improved activation technique

M Fisichella,A.C Shotter,D Torresi,A Di Pietro,M.G Pellegriti,V Scuderi,C Marchetta,E Strano,P Figuera,M Lattuada,A Musumarra,C Ruiz,M Zadro

doi:10.1051/epjconf/20146603027

Abstract

Fusion excitation functions have been measured for the 6 Li+120 Sn and 7 Li+119 Sn systems at energies around the Coulomb barrier, to investigate the effects of neutron transfer and breakup on the fusion process. At energies above the barrier, a suppression of the complete fusion excitation function with respect to the prediction of the 1D - Barrier Penetration Model has been observed, in both cases. At energies below the Coulomb barrier, no significant difference between the two excitation function, imputable to the different neutron transfer Q-values of the two systems has been observed.

Highlights

EPJ Web of Conferences that in reactions on heavy targets (Z > 62), due to the strong breakup channel eventually followed by incomplete fusion,one has a suppression of the complete fusion (CF) above the barrier [1,2,3]
By comparing the fusion excitation function for the two systems below the barrier, we wish to look for possible effects that could be attributed to the different neutron transfer Q-values
As in similar experiments [12,13,14,15], we measured the fusion excitation functions by using an activation technique, based on the off-line detection of the atomic X-rays emitted after the electron capture decay of the evaporation residues (ER) produced in the reaction

Summary

Introduction

Concerning the neutron transfer, a lot of theoretical and experimental studies have been done to investigate on the possible presence of the sub-barrier fusion cross section enhancement on the neutron transfer Q-value. Some signatures suggest that the presence of positive Q-values for neutron transfer enhances the fusion cross sections at sub-barrier energies

Results

Conclusion