Extended sudden approximation modeling of high-energy nucleon-removal reactions
Extended sudden approximation modeling of high-energy nucleon-removal reactions
复制标题
高能核子去除反应的扩展突然逼近模型
DOI：
10.1103/physrevc.70.054602
复制
发表时间：
2004
影响因子：
3.1
通讯作者：
A. Bonaccorso
中科院分区：
文献类型：
--
作者：
F. Cârstoiu;E. Sauvan;N. Orr;A. Bonaccorso
基于突变近似的计算已经被用来描述高能单核子去除反应。在这种方法中，它作为其出发点的形式主义开发来描述的分裂发达的单中子晕系统，核子去除截面和完整的三维动量分布的核心碎片，包括吸收，衍射，库仑，和核库仑干涉振幅，已被计算。库仑分裂已被处理到所有的订单偶极子相互作用。在这里的结果进行比较，实验数据的范围内的光，富中子的PSD壳核在43-68兆电子伏/核子的光束能量。良好的协议被发现的包容性截面和纵向和横向动量分布。在{sup 17}C的情况下，还与使用转移到连续模型的计算结果进行了比较。在突然近似模型计算的三维动量分布表现出强烈耦合的反应的s波状态的纵向和横向动量分量，而没有这样的效果是明显的d波。由于实验接受度有限，对横向动量的探测不完全，从而导致具有显著s波价中子组态的原子核的纵向动量分布变窄，这一点已被数据证实。更多»还探讨了衍射解离导致的纵向动量分布的不对称性。«少
Calculations based on the sudden approximation have been performed to describe high-energy single-nucleon removal reactions. Within this approach, which takes as its starting point the formalism developed to describe the breakup of well-developed single-neutron halo systems, the nucleon-removal cross section and the full three-dimensional momentum distributions of the core fragments, including absorption, diffraction, Coulomb, and nuclear-Coulomb interference amplitudes, have been computed. The Coulomb, breakup has been treated to all orders for the dipole interaction. The results are compared here to experimental data for a range of light, neutron-rich psd-shell nuclei taken at beam energies of 43-68 MeV/nucleon. Good agreement is found for the inclusive cross sections and both the longitudinal and transverse momentum distributions. In the case of {sup 17}C, comparison is also made with the results of calculations using the transfer-to-the-continuum model. The three-dimensional momentum distributions computed within the sudden approximation model exhibit longitudinal and transverse momentum components that are strongly coupled by the reaction for s-wave states, while no such effect is apparent for d waves. Incomplete detection of transverse momenta arising from limited experimental acceptances thus leads to a narrowing of the longitudinal distributions for nuclei with significant s-wave valence neutron configurations, as confirmed by the data.more » Asymmetries in the longitudinal momentum distributions attributed to diffractive dissociation are also explored.« less