Probing the fusion of neutron-rich nuclei with re-accelerated radioactive beams

Abstract

We report the first measurement of the fusion excitation functions for $^{39,47}$ K + $^{28}$Si at near-barrier energies. Evaporation residues resulting from the fusion process were identified by direct measurement of their energy and time of flight with high geometric efficiency. At the lowest incident energy, the cross section measured for the neutron-rich $^{47}$K -induced reaction is ≈ 6 times larger than that of the β -stable system. This experimental approach, both in measurement and in analysis, demonstrates how to efficiently measure fusion with low-intensity re-accelerated radioactive beams, establishing the framework for future studies.