Collaborative Research: Computational Faddeev approach to Nuclear Reactions

核科学的任务是回答这样的问题：(I)物质是如何形成的，它是如何演化的？(2)亚原子物质是如何组织起来的，出现了什么现象？(3)如何才能最好地利用核物理提供的知识和技术进步造福社会？提供这些问题的答案取决于对核反应的详细理论理解，在这个领域，当前的方法要么过时，要么局限于少数应用。在这个更大的背景下，这个项目将重点放在对重离子诱导反应的理论研究上。由于涉及奇异核的寿命短，与重元素来源相关的直接中子俘获测量通常是不可能的。间接技术，如氚诱导的反应，是提取相关天体物理率的常用工具。这些反应是放射束设施正在进行的实验计划的一部分，以及未来设施如稀有同位素束设施(FRIB)计划的一部分。因此，这个项目将为具有挑战性的实验项目提供理论支持，并将为研究生和博士后研究员提供一个独特的培训机会。可靠的反应理论对于理解使用(d，p)反应产生的实验项目产生的数据至关重要。从理论上讲，(d，p)反应很有吸引力，因为散射可以归结为一个有效的三体问题。由排斥库仑相互作用引起的三体核反应问题是求解核反应三体问题最具挑战性的方面之一。对于轻核，动量空间的Faddeev方程可以通过屏蔽库仑力来处理，而对于重系统，类似的方法很难实现。事实上，对于在FRIB产生的大多数新的奇异原子核来说，目前可用的计算方法是不够的。该项目将满足这一关键需求，并为三体核反应问题提供一种精确的Faddeev方法，在三体核反应问题中，库仑力将在没有筛选的情况下得到处理。

Nuclear Science is tasked with answering questions such as: (i) How did matter come into being and how does it evolve? (ii) How does subatomic matter organize itself and what phenomena emerge? (iii) How can the knowledge and technology progress provided by nuclear physics best be used to benefit society? Providing answers to these questions depends on a detailed theoretical understanding of nuclear reactions, a field in which current approaches are either outdated or limited to a small number of applications. In this larger context, this project will focus on the theoretical study of deuteron-induced reactions. Due to the short lifetimes involving exotic nuclei, direct neutron capture measurements of relevance to the origin of the heavy elements are often not possible. Indirect techniques like deuteron induced reactions are a common tool to extract the relevant astrophysical rates. These reactions are part of ongoing experimental programs at radioactive beam facilities, as well as programs at future facilities such as the Facility for Rare Isotope Beams (FRIB). As such, this project will provide theoretical support to challenging experimental programs and will provide a unique training opportunity for graduate students and post-doctoral fellows.A reliable reaction theory is critical for the understanding the data produced at experimental programs using (d,p) reactions. From a theoretical perspective, (d,p) reactions are attractive because the scattering can be reduced to an effective three-body problem. One of the most challenging aspects of solving the three-body problems for nuclear reactions is posed by the repulsive Coulomb interaction. While for light nuclei the momentum-space Faddeev equations can be treated by screening the Coulomb force, a similar approach is difficult to implement for heavy systems. Indeed, for most of the new exotic nuclei to be produced at FRIB, currently available computational methods are not adequate. This project will address this critical need and provide an implementation of an exact Faddeev method for the three-body nuclear reaction problem, in which the Coulomb force will be treated without screening.