Resonant Few-Body Systems from the Lattice

晶格共振少体系统

基本信息

批准号：
2012289
负责人：
Michael Doering
金额：
$ 36万
依托单位：
George Washington University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012289&HistoricalAwards=false
关键词：
Resonant Few Body Systems Lattice

项目摘要

Strong forces are responsible for the formation of matter as we know it, but the precise mechanism of how this occurs remain a mystery. Strong forces bind nucleons together in atomic nuclei, but they also lead to the emergence of resonant phenomena at higher energies that are studied, e.g., at the Thomas Jefferson National Accelerator Facility (JLab). The experimental and theoretical quest for resonances to understand the strong force focuses on few-body systems and their dynamics. This project aims at closing the gap between theoretical calculations on few-body systems, called lattice QCD, and phenomenology. The main technical challenge addressed in this proposal concerns the problem that these calculations are performed in a small cubic volume instead of infinite space, and how to remove the corresponding artifacts so that lattice QCD can be compared to Nature. Deviations of these predictions from measurements are hints for new physics. The project also aims to conceptually improve the analysis of three-body data from experiment. The PI will in parallel develop simulations of simple quantum mechanical systems to illustrate the undergraduate and graduate curriculum along the lines of standard textbooks to help develop a diverse, globally competitive STEM workforce.The theory underlying the strong force, Quantum Chromodynamics (QCD), can be calculated using Lattice QCD. However, finite-volume effects for the case of three particles are poorly understood. This project aims to further develop three-body methods to enable the extrapolation of Lattice QCD results to the physical world and to help answer fundamental questions regarding QCD predictions for the properties of excited mesons and baryons. For this, the principle of unitarity, related to the conservation of probability in nuclear reactions, can be efficiently used as the guiding principle, and can be extended to the three- or more particle sector. In this project, methods will be conceptually upgraded to be applied to emblematic resonances. To highlight one, the Roper resonance has been under investigation for decades due to its unusually light mass and its debated nature as radial excitation of the nucleon or hadronic molecule. Furthermore, there is no clear signal for it in ab-initio lattice QCD calculations. The focus of this project is to quantify the finite-volume effects to solve this puzzle. Other lines of investigation address axial resonances that, in their three-body dynamics, resemble the supposed exotic mesons – a new type of particle sought for at JLab and other experiments.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.

正如我们所知，强力是物质形成的原因，但其发生的确切机制仍然是个谜，强力将原子核中的核子结合在一起，但它们也会导致更高能量下共振现象的出现。例如，在托马斯·杰斐逊国家加速器设施（JLab）研究了通过实验和理论来了解强力的研究，该项目的重点是少体系统及其动力学。身体该提案解决的主要技术挑战涉及这些计算是在小立方体积而不是无限空间中执行的问题，以及如何消除相应的伪影，以便将晶格 QCD 与现象学进行比较。这些预测与测量的偏差为新物理学提供了线索，该项目还旨在从概念上改进对实验数据的分析，PI 将同时开发简单量子力学系统的模拟，以说明本科生和学生的情况。按照标准教科书的课程进行毕业，以帮助培养一支多元化的、具有全球竞争力的 STEM 劳动力队伍。强作用力的基础理论，量子色动力学 (QCD)，可以使用晶格 QCD 进行计算。但是，对于三个的情况，有限体积效应。该项目旨在进一步开发三体方法，将晶格 QCD 结果外推到物理世界，并帮助回答有关激发介子和 QCD 性质的预测的基本问题。为此，与核反应中概率守恒相关的幺正性原理可以有效地用作指导原理，并且可以扩展到三个或更多粒子扇区。在这个项目中，方法将在概念上进行。需要强调的是，罗珀共振由于其异常轻的质量及其作为核子或强子分子的径向激发的争议性质，已经被研究了几十年。此外，还没有明确的信号。该项目的重点是量化有限体积效应以解决这个难题，其他研究方向解决了轴向共振，这些共振在三体动力学中类似于所谓的奇异介子。 JLab 和其他实验寻求的新型粒子。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Multi-particle systems on the lattice and chiral extrapolations: a brief review

DOI：
10.1140/epjs/s11734-021-00146-5
发表时间：
2021-02
期刊：
The European Physical Journal Special Topics
影响因子：
0
作者：
M. Mai;M. Döring;A. Rusetsky
通讯作者：
M. Mai;M. Döring;A. Rusetsky

Three-Body Dynamics of the a1(1260) Resonance from Lattice QCD

晶格 QCD 的 a1(1260) 共振的三体动力学

DOI：
10.1103/physrevlett.127.222001
发表时间：
2021
期刊：
Physical Review Letters
影响因子：
8.6
作者：
Mai, Maxim;Alexandru, Andrei;Brett, Ruairí;Culver, Chris;Döring, Michael;Lee, Frank X.;Sadasivan, Daniel
通讯作者：
Sadasivan, Daniel

Finite-volume energy spectrum of the K−K−K− system