Systematic study of breakup effects on complete fusion at energies above the Coulomb barrier

Abstract

A large number of complete fusion excitation functions of reactions including the breakup channel were measured in recent decades, especially in the last few years. It allows us to investigate the systematic behavior of the breakup effects on the complete fusion cross sections. To this end, we perform a systematic study of the breakup effects on the complete fusion cross sections at energies above the Coulomb barrier. The reduced fusion functions F (x) are compared with the universal fusion functions which are used as a uniform standard reference. The complete fusion cross sections at energies above the Coulomb barrier are suppressed by the breakup of projectiles. This suppression effect for reactions induced by the same projectile is independent of the target and mainly determined by the lowest energy breakup channel of the projectile. There holds a good exponential relation between the suppression factor and the energy corresponding to the lowest breakup threshold.

Recent developments in fusion and direct reactions with weakly bound nuclei

“…Very recently, Wang et al [399] performed a comprehensive investigation of the suppression of CF in collisions at energies slightly above the barrier. They considered collisions of the 6,7 Li, 9 Be, 10,11 B, 12,13 C and 16 O projectiles with several heavy targets, ranging from 89 Y to 209 Bi.…”

Systematics of capture and fusion dynamics in heavy-ion collisions

“…Since we focus on the capture and fusion dynamics around the Coulomb barrier, only the reaction systems for which capture excitation functions are measured in this energy region are considered in this work. Note that reaction systems with weakly bound nuclei involved are also excluded, because the coupling to the breakup channel is very complicated, especially in the sub-barrier region [110][111][112][113][114][115][116][117][118][119][120][121][122][123]. Actually, in Ref.…”

Classical dynamical modelling of near-barrier breakup

“…Direct excitation of the intrinsic cluster continuum of the projectile is one possible trigger of breakup. Indeed, many works have noted a correlation between the direct breakup threshold and the degree of fusion suppression [19,20]. This correlation is apparent not only for weakly-bound stable nuclides such as 6,7 Li, 9 Be and 6 He, but also for more well-bound nuclides such as 10,11 B, 12,13 C and 16 O.…”