Ab Initio Nuclear Structure and Reactions for Astrophysics and Neutrino Physics

天体物理学和中微子物理学的从头算核结构和反应

基本信息

批准号：
1913728
负责人：
Kristina Launey
金额：
$ 27.13万
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：
2019
资助国家：
美国
起止时间：
2019-08-15 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1913728&HistoricalAwards=false
关键词：
Ab Initio Nuclear Structure Reactions

项目摘要

Following the history-making discovery of nuclear fission, which manifested the huge amount of energy that is released by breaking the strong bonds between neutrons and protons, nuclear physicists have searched for ever more comprehensive explanations of the properties of the atomic nucleus. Such advances are critical to predict exotic nuclei in processes under extreme conditions as stellar mergers and explosions, and to probe neutrino-related processes. The recent advent of radioactive beam facilities has enabled exotic-nuclei measurements, based on collisions of nuclei and their reactions. To predict inaccessible nuclei, these reactions must be well understood and modeled. However, exact solutions exist up to about five particles. The goal of this project is to expand dramatically the capabilities of nuclear reaction theory, by providing input to reaction simulations that are grounded in first principles, but can also accommodate heavier nuclei and enhanced deformation. The latter can help study the origin of elements and neutrino properties, two of the biggest challenges in nuclear physics today. The project will have a wider impact because nuclear energy and national security research has similar needs. Future leaders (postdocs and students) will be trained in low-energy nuclear science and petascale computing, while preparing a web-database for research and educational purposes.The overarching goal is to learn from and inform experiments at radioactive beam facilities, and to predict properties of experimentally inaccessible nuclei that are key to advancing our knowledge about astrophysical processes and neutrino physics. The program targets to improve reaction modeling, by constructing the effective interaction between a target and a projectile from first principles (historically, referred to as an optical potential and fitted to experimental data), and thus to account for the challenging microscopic structure of the participating nuclei. As these interactions are an essential input to numerous reaction models that are currently in use, the new developments will serve as an important tool in a broad spectrum of studies. The project will capitalize on a symmetry-guided approach that, by exploiting symmetries known to dominate the dynamics, has enabled ab initio investigations of heavier nuclear species, deformed or not. In this approach, all participating particles are treated on the same footing within a "shell model" picture, while employing chiral effective field theory interactions between protons and neutrons. The end products will include calculations of beta decays in nuclei of enhanced deformation, and of reaction observables, e.g., cross sections for scattering, charge-exchange, and (d,p) reactions, of importance to astrophysics.This project advances the objectives of "Windows on the Universe: the Era of Multi-Messenger Astrophysics", one of the 10 Big Ideas for Future NSF Investments.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.

核裂变的历史性发现表明，中子和质子之间的强力键断裂会释放出巨大的能量，继这一发现之后，核物理学家一直在寻找对原子核性质的更全面的解释。这些进展对于预测恒星合并和爆炸等极端条件下过程中的奇异核以及探测中微子相关过程至关重要。最近出现的放射性束设施使得基于核碰撞及其反应的外来核测量成为可能。为了预测不可接近的核，必须很好地理解和建模这些反应。然而，精确解最多存在五个粒子。该项目的目标是通过为基于第一原理的反应模拟提供输入，显着扩展核反应理论的能力，但也可以适应更重的核和增强的变形。后者可以帮助研究元素的起源和中微子特性，这是当今核物理学面临的两个最大挑战。该项目将产生更广泛的影响，因为核能和国家安全研究有类似的需求。未来的领导者（博士后和学生）将接受低能核科学和千万亿级计算方面的培训，同时准备用于研究和教育目的的网络数据库。总体目标是从放射性束设施的实验中学习并为实验提供信息，并预测实验上无法接近的原子核的特性对于增进我们对天体物理过程和中微子物理学的了解至关重要。该计划的目标是通过根据第一原理（历史上称为光学势并适合实验数据）构建目标和射弹之间的有效相互作用来改进反应建模，从而解释参与的具有挑战性的微观结构原子核。由于这些相互作用是当前使用的众多反应模型的重要输入，因此新的发展将成为广泛研究的重要工具。该项目将利用对称引导的方法，通过利用已知的主导动力学的对称性，可以对较重的核素（无论是否变形）进行从头开始的研究。在这种方法中，所有参与的粒子都在“壳模型”图中以相同的基础进行处理，同时采用质子和中子之间的手性有效场论相互作用。最终产品将包括增强形变核中 β 衰变的计算，以及反应可观测值的计算，例如对天体物理学很重要的散射、电荷交换和 (d,p) 反应的横截面。 “宇宙之窗：多信使天体物理学时代”，NSF 未来投资十大创意之一。该奖项反映了 NSF 的法定使命，并被认为值得通过以下方式支持：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。

项目成果

期刊论文数量（23）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Nuclear spin features relevant to ab initio nucleon-nucleus elastic scattering

与从头开始核子-核弹性散射相关的核自旋特征

DOI：
10.1103/physrevc.103.054314
发表时间：
2021
期刊：
Physical Review C
影响因子：
3.1
作者：
Baker, R. B.;Burrows, M.;Elster, Ch.;Launey, K. D.;Maris, P.;Popa, G.;Weppner, S. P.
通讯作者：
Weppner, S. P.

Efficacy of the symmetry-adapted basis for ab initio nucleon-nucleus interactions for light- and intermediate-mass nuclei

轻质量和中等质量核的从头算核子-核相互作用的对称性适应基础的有效性

DOI：
10.1016/j.cpc.2022.108476
发表时间：
2022
期刊：
Computer Physics Communications
影响因子：
6.3
作者：
Mercenne, A.;Launey, K.D.;Dytrych, T.;Escher, J.E.;Quaglioni, S.;Sargsyan, G.H.;Langr, D.;Draayer, J.P.
通讯作者：
Draayer, J.P.

Emergent symmetries in atomic nuclei: Probing nuclear dynamics and physics beyond the standard model

原子核中的涌现对称性：超越标准模型探索核动力学和物理学

DOI：
10.21468/scipostphysproc.14.007
发表时间：
2023
期刊：
SciPost Physics Proceedings
影响因子：
0
作者：
Launey, Kristina D.;Becker, K. S.;Sargsyan, G. H.;Molchanov, O. M.;Burrows, M.;Mercenne, A.;Dytrych, T.;Langr, D.;Draayer, J. P.
通讯作者：
Draayer, J. P.

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