RII Track-4: Ab initio modeling of nuclear reactions for studies of nucleosynthesis and fundamental symmetries in nature

RII Track-4：核反应从头开始建模，用于研究核合成和自然界的基本对称性

• 批准号: 1738287
• 负责人: Kristina Launey
• 金额: $ 27.21万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-15 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1738287&HistoricalAwards=false
• 关键词: RII; Track; Ab; initio; modeling

Non-technical DescriptionEver since the history-making discovery of nuclear fission, which demonstrated the huge amount of energy that can be released when the strong bonds between the atomic constituents (neutrons and protons) are broken, theoretical nuclear physicists have searched for a comprehensive explanation of the properties of the atomic nucleus based on knowledge of the strong force between these constituents. This project takes advantage of the instrumentation, computing capabilities, and theoretical expertise at the Lawrence Livermore National Laboratory (LLNL) to develop a theoretical framework that will improve our understanding of these forces. When this goal is achieved, it will be possible to predict reactions that take place under extreme conditions, from stellar explosions to the interior of nuclear reactors. Improving our knowledge of nuclear reactions will help us further understand 'nuclei-fueled' astrophysical processes, and safely and economically harness nuclear phenomena in support of the broad scope of humanitarian needs. Future advances in nuclear science and technology hold promise for a growing number of applications for medicine, industry, energy, and national security. The development of advanced instrumentation and applications of nuclear isotopes in disease treatments provide two prominent examples that rely on elementary properties of atomic nuclei. In addition to providing access to the facilities and expertise at LLNL, this project will provide training and unique research experiences for the PI and a postdoctoral fellow, with indirect benefits to graduate and undergraduate students. Technical DescriptionThis project aims to dramatically expand the reach as well as the impact of nuclear reaction theory with the aim of predicting properties of experimentally inaccessible nuclei and reactions, while supporting and informing experiments at current and upcoming radioactive beam facilities. The goal is to develop and implement a symmetry-guided theory that will enable pioneering ab initio investigations of reactions for heavier nuclear species, while accounting for the challenging structure of the participating nuclei. This will be achieved by capitalizing on approximate symmetries known to dominate in nuclei. In this approach all participating particles in the target and incoming proton or neutron are treated on the same footing within a 'shell model' concept of the quantum many-particle system and the compound nucleus. In addition, state-of-the-art chiral effective field theory interactions between protons and neutrons will be employed. New predictions, possible through the unique combination of expertise of theoretical and experimental nuclear physicists at Louisiana State University and LLNL are anticipated for processes inaccessible to experiments, which can facilitate neutrino- and fusion-related research and are key to advancing knowledge about astrophysical processes, as well as of fundamental symmetries in nature. This, in turn, can help address two of the most fundamental questions of physics today: the origin of elements, and if the neutrino is its own antiparticle. While the proposed applications focus on specific important questions, the new developments will have wider impact, as multi-physics simulations in the areas of nuclear energy and national security have similar needs. As part of this research, future leaders will be trained in research in low-energy nuclear science, while learning and working in massively parallel environments at petascale computing facilities.

自从历史创造核裂变以来，非技术描述曾经表明，当原子成分（中子和质子）之间的牢固键被破坏时，可以释放出大量的能量，理论核物理学家已经根据这些组成师之间的强大力量进行了对原子核的特性的全面解释。该项目利用劳伦斯·利弗莫尔国家实验室（LLNL）的仪器，计算能力和理论专业知识来开发一个理论框架，以提高我们对这些力量的理解。当实现这一目标时，将有可能预测在极端条件下发生的反应，从恒星爆炸到核反应堆的内部。提高对核反应的了解将有助于我们进一步了解“核燃料”的天体物理过程，并安全，经济利用核现象，以支持人道主义需求的广泛范围。核科学和技术的未来进步对医学，工业，能源和国家安全的越来越多的应用有望。核同位素在疾病治疗中的高级仪器的发展提供了两个依赖原子核基本特性的突出例子。除了提供LLNL的设施和专业知识的访问外，该项目还将为PI和博士后研究员提供培训和独特的研究经验，并为研究生和本科生提供间接利益。技术描述该项目旨在大大扩展覆盖范围以及核反应理论的影响，目的是预测实验性无法接近的核和反应的性质，同时支持和告知实验在当前和即将放射性光束设施上。 目的是开发和实施一种对称引导理论，该理论能够对较重的核物种的反应进行开创性研究，同时考虑到参与核的具有挑战性的结构。这将通过利用已知在核中占主导地位的近似对称性来实现。在这种方法中，在量子多粒子系统和化合物核的“壳模型”概念中，在同一基础上对目标和中性质子或中子的所有参与粒子进行处理。此外，将采用质子和中子之间的最先进的手性有效现场理论相互作用。预计通过实验无法访问的过程，预计路易斯安那州立大学和LLNL的理论和实验核物理学家的专业知识的独特组合可能会做出新的预测，这可以促进中微子和融合融合相关的研究，并且是促进有关天体物理学过程的知识以及基本及其基本及其本质上的知识的关键。反过来，这可以帮助解决当今物理学中最基本的两个问题：元素的起源，以及中微子是否是其自身的反粒子。尽管拟议的应用程序集中在特定的重要问题上，但新的发展将产生更大的影响，因为核能和国家安全领域的多物理模拟也有类似的需求。作为这项研究的一部分，未来的领导者将接受低能核科学研究的培训，同时在Petascale Computing设施的大规模平行环境中学习和工作。

项目成果

Benchmark calculations of electromagnetic sum rules with a symmetry-adapted basis and hyperspherical harmonics

• DOI: 10.1103/physrevc.102.014320
• 发表时间: 2020-03
• 期刊: arXiv: Nuclear Theory
• 作者: R. Baker;K. Launey;S. Bacca;N. Dinur;T. Dytrych

No-core Symplectic Model: Exploiting Hidden Symmetry in Atomic Nuclei

• DOI: 10.1088/1742-6596/863/1/012008
• 发表时间: 2017-06
• 期刊: Journal of Physics: Conference Series
• 作者: J. Draayer;K. Launey;T. Dytrych;A. Dreyfuss;R. Baker;M. Miora

Ab initio folding potentials for nucleon-nucleus scattering based on no-core shell-model one-body densities

基于无核壳模型单体密度的核子-核散射的从头计算折叠势

• DOI: 10.1103/physrevc.99.044603
• 发表时间: 2019
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Burrows, M.;Elster, Ch.;Weppner, S. P.;Launey, K. D.;Maris, P.;Nogga, A.;Popa, G.
• 通讯作者: Popa, G.

Efficient algorithm for representations of U(3) in U(N)

U(3) 在 U(N) 中表示的高效算法

• DOI: 10.1016/j.cpc.2019.05.018
• 发表时间: 2019
• 期刊: Computer Physics Communications
• 影响因子: 6.3
• 作者: Langr, Daniel;Dytrych, Tomáš;Draayer, Jerry P.;Launey, Kristina D.;Tvrdík, Pavel
• 通讯作者: Tvrdík, Pavel

SU3lib: A C++ library for accurate computation of Wigner and Racah coefficients of SU(3)

SU3lib：用于精确计算 SU(3) 的 Wigner 和 Racah 系数的 C 库

• DOI: 10.1016/j.cpc.2021.108137
• 发表时间: 2021
• 期刊: Computer Physics Communications
• 影响因子: 6.3
• 作者: Dytrych, Tomáš;Langr, Daniel;Draayer, Jerry P.;Launey, Kristina D.;Gazda, Daniel
• 通讯作者: Gazda, Daniel