Applications of Nuclear Structure Theory

原子核的性质对于我们理解物理学的许多领域是必不可少的。在最基本的层次上，原子核是由通过胶子交换而结合在一起的夸克组成的。夸克分为重子和介子，这为我们理解原子核是由质子和中子通过交换介子而结合在一起提供了基础。稳定同位素提供大约250种不同的质子和中子组合。在实验室里又进行了大约3，000种组合，还有更多的组合，特别是那些中子大量过剩的组合，将在下一代设施中进行研究，如密歇根州立大学的稀有同位素束设施。在宇宙的演化过程中，有多达7,000种不同的质子和中子组合参与了元素的形成。核结构理论的这个项目将提供分析模型和计算工具，以了解这些核的性质。这些研究成果将应用于基础物理和核天体物理等需要核性质的领域，极大地拓展组态相互作用（CI）和能量密度泛函（EDF）模型在原子核中的应用。这将在几个层面上进行。PI将开发用于这些方法的新的哈密顿量，这些方法的输入来自基于核子-核子散射数据的从头算模型，以及来自已知实验数据的经验约束。PI将开发计算方法，考虑到CI方法中所需的非常大的基础尺寸，允许解决量子多体问题。PI将把这些结果应用到物理学的许多领域。它们将用于与FRIB和其他实验室的实验项目合作。它们将被用来获得核矩阵元素，用于研究原子核的基础物理。它们还将与MSU的核天体物理学联合研究所和元素演化中心（JINA-CEE）合作，计算理解超新星和X射线爆发所需的反应速率，以及中子星和中子星星合并所需的核状态方程。该项目支持的研究生将有独特的机会培训和促进高知名度的核理论研究。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

The properties of atomic nuclei are essential for our understanding of many areas of physics. At the most fundamental level, nuclei are composed of quarks held together by the exchange of gluons. The grouping of quarks into baryons and mesons provides the ingredients for our understanding of nuclei as being composed of protons and neutrons held together by the exchange of mesons. The stable isotopes provide about 250 different combinations of protons and neutrons. About 3,000 more combinations have been made in the laboratory, and many more, in particular those with a large excess of neutrons, will be made and studied at the next generation of facilities such as the Facility for Rare Isotope Beams (FRIB) at Michigan State University. Up to 7,000 different combinations of protons and neutrons were involved in the formation of the elements during the evolution of the universe. This project in nuclear structure theory will provide analytical models and computational tools for understanding the properties of these nuclei. The results of these studies will be applied to areas of fundamental physics and nuclear astrophysics where the nuclear properties are needed.This project will greatly expand the use of of Configuration Interaction (CI) and Energy Density Functional (EDF) models for nuclei. This will carried out on several levels. The PI will develop new Hamiltonians used for these methods with input from ab-initio models based on nucleon-nucleon scattering data together with empirical constraints from known experimental data. The PI will develop computational methods that allow for the solution of the quantum many-body problem that take into account the very large basis dimensions needed in the CI method. The PI will make applications of these results to many areas of physics interest. They will be used for collaborations with the experimental program at FRIB and other laboratories. They will be used to obtain nuclear matrix elements for studying fundamental physics with nuclei. They also will be used in collaboration with the Joint Institute for Nuclear Astrophysics and Center for the Evolution of the Elements (JINA-CEE) at MSU to calculate reaction rates needed for understanding supernovae and X-ray bursters, and for the nuclear equations of state needed for neutron stars and neutron star mergers. The graduate students supported by this project will have unique opportunities to train and contribute to high-profile research in nuclear theory.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.