Projectile breakup dynamics for $^{6}$Li + $^{59}$Co: kinematical analysis of $α$-$d$ coincidences
F. A. Souza, N. Carlin, C. Beck, N. Keeley, A. Diaz-Torres, R. Liguori Neto, C. Siqueira-Mello, M. M. de Moura, M. G. Munhoz, R. A. N. Oliveira, M. G. Del Santo… 展开作者
F. A. Souza, N. Carlin, C. Beck, N. Keeley, A. Diaz-Torres, R. Liguori Neto, C. Siqueira-Mello, M. M. de Moura, M. G. Munhoz, R. A. N. Oliveira, M. G. Del Santo, A. A. P. Suaide, E. M. Szanto, A. Szanto de Toledo
备注：
Revised version including new Fig.3 and Fig.4 with new CDCC calculations. Accepted for publication at Eur. Phys. Jour. A. 11 pages, 6 figures
本文研究了轰击能量为$E_{lab} = 29.6$ MeV的$^{6}$ Li + $^{59}$ Co体系中$α$ - $d$符合的运动学。通过在不同的角度间隔上进行排他性的测量，可以识别顺序射弹分裂和直接射弹分裂分量的各自贡献。使用半经典的方法，这些过程的仔细分析提供了关于它们的寿命和它们相对于目标的发生距离的信息。分裂到低洼（近阈值）连续延迟，并发生在大的核间距离。这表明，弹丸破碎对完全聚变过程的影响，可以基本上与直接破碎的$^6$锂高位连续谱。%
英文摘要：
A study of the kinematics of the $α$-$d$ coincidences in the $^{6}$Li + $^{59}$Co system at a bombarding energy of $E_{lab} = 29.6$ MeV is presented. With exclusive measurements performed over different angular intervals it is possible to identify the respective contributions of the sequential projectile breakup and direct projectile breakup components. A careful analysis using a semiclassical approach of these processes provides information on both their lifetime and their distance of occurrence with respect to the target. Breakup to the low-lying (near-threshold) continuum is delayed, and happens at large internuclear distances. This suggests that the influence of the projectile breakup on the complete fusion process can be related essentially to direct breakup to the $^6$Li high-lying continuum spectrum. %
The virtual photon theory (VPT), which is based on first-order Coulomb dissociation restricted to the electric dipole ($E1$), has been successfully used to explain the breakup data for several cases. Our aim is to study the role of various higher-order processes that are ignored in the VPT, such as the nuclear breakup, interference between nuclear and Coulomb amplitudes, and multistep breakup processes mainly due to strong continuum-continuum couplings in the breakup of two-body projectiles on a heavy target at both intermediate and higher incident energies. For the purpose of numerical calcul…
The production of $α$-particles in reactions using both the strongly and weakly bound projectiles at energies around the Coulomb barrier show several interesting features. To understand these, the role of various reaction mechanisms responsible for $α$-production, such as non-capture breakup, capture of only one of the fragments subsequent to projectile breakup and their contribution to reaction cross sections have been investigated. A systematic study of the $α$-particle production based on available data for various projectile target systems have been performed and a classification based on …
Influence of projectile <alpha>- breakup threshold on complete fusion
11，10B +159Tb的完全聚变激发已经在各自的库仑势垒附近的能量下测量，并且现有的7Li+159Tb的完全聚变测量已经扩展到更高的能量。测量结果表明，显着减少的完全融合截面在势垒以上的能量为两个反应，10 B +159 Tb和7 Li +159 Tb，当与那些为11 B +159 Tb。比较表明，完全融合截面的抑制程度与弹丸<alpha>的分离能有关。此外，这两个反应，10 B +159 Tb和7Li+159 Tb被发现产生不完全的融合产物在各自的库仑势垒附近的能量，<alpha>与粒子发射通道是有利的不完全融合过程中的两种情况下。
Accurate knowledge of the response of the detection system is very crucial for unambiguous interpretation of the experimental data. A simulation code has been developed using the Monte Carlo technique involving 3-body kinematics for the analysis of data obtained with segmented large area Si $ΔE-E$ detector telescopes in nuclear reaction measurements. Care was taken in the analysis to maximize the angular coverage and statistics. The emphasis is placed to extract the absolute cross sections of the different reaction processes, for which coincident measurements are unavoidable. The estimated det…
