Breakup and Incomplete Fusion Reactions in ⁷Be + ²⁰⁸Pb

Light, weakly-bound nuclei reacting with heavy targets at energies above the fusion barrier are observed to have significant suppression of complete fusion when compared with single-barrier penetration models [1][2]. This suppression is accompanied by incomplete fusion yields, where only partial charge capture occurs. Prior measurements of breakup yields and characteristic timescales show that this cannot be explained by projectile breakup or transfer-triggered breakup reactions alone [3][4][5].

Instead, direct cluster transfer has been proposed as an alternative mechanism, consistent with measured α yields resulting from incomplete fusion [3]. These reaction dynamics are influenced by the projectile’s clustering structure and weak-binding, which plays a more significant role away from stability [6][7][8]. Therefore, to continue probing this interplay, we measured the breakup and fusion of ⁷Be on ²⁰⁸Pb at above barrier energies. By comparing the breakup of ⁷Be and its mirror nucleus, ⁷Li, we can decouple the effects of structure and weak-binding in complete fusion suppression. The ongoing analysis of the ⁷Be breakup data will be discussed.

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