Nuclear Reaction and Structure Studies with Radioactive and Stable beams

该项目涉及利用短寿命放射性原子核束研究核反应，同时发展仪器和技术以促进这些研究。具体的实验将着重研究接近核稳定性极限的富含中子和质子的核。这些弱束缚系统中有几个已经被证明发展出一种奇特的“核晕”结构，导致有效的核尺寸比基于更正常系统的性质预期的要大得多。我们感兴趣的是这种结构对由“晕”核引起的核反应的影响。该项目开发的氘化闪烁体中子探测器可能应用于国家安全计划。此外，我们计划使用特定的核反应来探测原子核的结构，这对理解中微子双β衰变很重要。为了寻找这种奇特的衰变模式，一些大规模而昂贵的实验正在进行中，这种模式将代表超越所谓粒子相互作用标准模型的物理学。如果观测到，这种衰变模式也将提供一种直接测量中微子质量的方法，这对高能物理、天文学和宇宙学等学科都很重要。然而，这种应用需要对参与衰变过程的原子核结构有更深入的了解。我们计划进行的实验将有助于发展这种认识。除了已经提到的仪器开发对国家安全问题的贡献之外，该项目更广泛的影响还包括通过研究生、本科生和高中学生参与世界一流的科学研究，培养具有科学素养的劳动力。这些小组有机会在核加速器、超导离子光学系统、辐射探测和其他技术方面进行实践培训。本科生来自圣母大学和密歇根大学，也来自中西部的几所本科大学和学院。这个高中项目包括公开讲座和其他外联活动，旨在突出核科学及其在考古和医学等其他领域的应用。最后，该项目有一个国际组成部分，包括与墨西哥和巴西的物理学家密切合作，并提议与英国、法国和意大利等国的物理学家进行新的合作。

This project involves the study of nuclear reactions utilizing beams of short-lived radioactive nuclei, together with the development of instrumentation and techniques to facilitate these investigations. Specific experiments will emphasize the study of neutron- and proton-rich nuclei near the limits of nuclear stability. Several of these weakly bound systems have been shown to develop an exotic "nuclear halo" structure, leading to an effective nuclear size that is much larger than expected based on the properties of more normal systems. Our interest is in the effect that this structure has on nuclear reactions induced by "halo" nuclei." The development of deuterated-scintillator neutron detectors for this project may have applications to national-security programs. In addition, we plan to use specific nuclear reactions to probe the structure of nuclei that are important for the understanding of neutrinoless double beta decay. Several massive and expensive experiments are underway to search for this exotic decay mode, which would represent physics beyond the so-called standard model of particle interactions. If observed, this decay mode would also present a means to directly measure the mass of the neutrino, which is important for subjects such as high-energy physics, astronomy, and cosmology. However, this application requires much-improved knowledge of the structure of the nuclei involved in the beta-decay process. The experiments we are planning to carry out will contribute to the development of this understanding.In addition to the already-mentioned contributions of instrumentation development to national-security issues, the broader impact of this project extends to the development of a scientifically-literate workforce via the involvement of students at the graduate, undergraduate, and high-school levels in world-class scientific research. These groups are afforded opportunities for hands-on training in nuclear accelerators, superconducting ion-optical systems, radiation detection, and other technologies. The undergraduate students come from Notre Dame and the University of Michigan, and also from several primarily-undergraduate universities and colleges in the Midwest. The high-school program includes public lectures and other outreach activities designed to highlight nuclear science and its applications to other fields such as archaeology and medicine. Finally, the program has an international component involving close collaborations with physicists in Mexico and Brazil, and new collaborations including the UK, France, and Italy are proposed.