Fusion versus Breakup: Observation of Large Fusion Suppression

Complete fusion excitation functions for 9 Be + 208 Pb have been measured to high precision at near barrier energies. The experimental fusion barrier distribution extracted from these data allows reliable prediction of the expected complete fusion cross-sections. However, the measured cross-sections are only 68% of those predicted. The large cross-sections observed for incomplete fusion products support the interpretation that this suppression of fusion is caused by 9 Be breaking up into charged fragments before reaching the fusion