Further investigation on the fusion of ^(6)Li with ^(209)Bi target at near-barrier energies

The complete and incomplete fusion cross sections for ^(6)Li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb barrier.The cross sections of(deuteron captured)incomplete fusion(ICF)products were re-quantified experimentally for this reaction system.The results reveal that the ICF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CDCC)method was performed for the aforementioned CF and ICF cross sections;the result is consistent with the experiments.The universal fusion function(UFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

Fusion and one-neutron stripping process for ^(6)Li+^(94)Zr system around the Coulomb Barrier

The complete and incomplete fusion cross section as well as one-neutron stripping process of ^(6)Li+^(94)Zr system were measured at the energies around the Coulomb barrier by onlineγ-ray method.In addition to a 30%suppression factor when compared with the measured total fusion process,the complete fusion cross section in ^(6)Li+^(94)Zr system was observed to be significantly lower than those in the nearby ^(6)Li+^(90,96)Zr system.The new experimental result implies that the coupling with breakup channel in the ^(6)Li-induced fusion processes can be affected by the inner structure of the target,which is still not clear in any available model calculation.For the one-neutron stripping process,the direct production cross sections for each level in 95Zr were extracted and compared with the coupled reaction channel calculation,offering a unique opportunity to examine the single-particle nature of the produced excited states.Given the fact that an overall overestimation of the production cross section for 954-keV and1618-keV levels was observed in the comparison,further investigation is highly demanded in order to understand the full reaction mechanism for the one-neutron stripping process induced by ^(6)Li.

CDCC calculations of fusion of 6Li with targets 144Sm and 154Sm：effect of resonance states

Continuum Discretized Coupled-Channel（CDCC） model calculations of total, complete and incomplete fusion cross sections for reactions of the weakly bound 6Li with 144,154Sm targets at energies around the Coulomb barrier are presented. In the cluster structure frame of 6Li→α＋d, short-range absorption potentials are considered for the interactions between the ground state of the projectile 6Li and α-d fragments with the target. In order to separately calculate complete and incomplete fusion and to reduce double-counting, the corresponding absorption potentials are chosen to be of different range. Couplings to low-lying excited states 2＋, 3-of 144Sm and 2＋, 4＋ of 154Sm are included. So, the effect on total fusion from the excited states of the target is investigated. Similarly, the effect on fusion due to couplings to resonance breakup states of 6Li, namely, l = 2,Jπ= 3＋, 2＋, 1＋ is also calculated.The latter effect is determined by using two approaches,（a） by considering only resonance state couplings and（b）by omitting these states from the full discretized energy space. Among other things, it is found that both resonance and non-resonance continuum breakup couplings produce fusion suppression at all the energies considered.