Multi-Hadron Interactions using Lattice QCD with the Stochastic LapH Method

质子和中子组成原子核，由称为夸克和胶子的基本粒子组成，它们的相互作用由量子色动力学(QCD)描述。这一理论表明，自然界中许多其他类型的复合粒子，即强子，应该以不稳定共振的形式存在。QCD预测的某些强子共振的性质将使用大规模计算资源进行研究。这项拟议的研究为目前的实验提供了支持，例如托马斯·杰斐逊国家加速器设施(JLab)D厅的GlueX实验。核子的结构和涉及一个被称为德尔塔重子的特定强子的散射将是另一个焦点。这些散射信息将对研究中微子的实验至关重要，中微子是一种弥漫在宇宙中的重要基本粒子。PI将指导一名从事这项研究的研究生，该研究生还将接受使用最先进的并行计算资源的培训。强子-强子相互作用的物理将使用时空格子上涉及夸克场和胶子场的路径积分的蒙特卡罗估计来研究。将计算核子-π、核子-核子和核子-超子散射相移，从而产生关于强子结构的重要信息。还将考虑涉及核子-π介子-π介子的散射过程。新的计算技术，如随机LAPH方法，使得在晶格QCD中进行这样的计算成为可能，这涉及到估计多强子和激发态算符的时间关联矩阵。涉及核子和通过德尔塔重子跃迁的形状因子将是一个特别关注的问题，因为它们对基于加速的中微子实验至关重要，例如深层地下中微子实验(DUNE)。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Protons and neutrons, which make up atomic nuclei, are comprised of fundamental particles known as quarks and gluons, whose interactions are described by quantum chromodynamics (QCD). This theory suggests that many other types of composite particles, known as hadrons, should exist in Nature as unstable resonances. The properties of certain hadronic resonances as predicted by QCD will be investigated using large-scale computing resources. The proposed research lends support to current experiments, such as the GlueX experiment in Hall D at the Thomas Jefferson National Accelerator Facility (JLab). The structure of the nucleon and scattering involving one particular hadron known as a Delta baryon will be another focus. This scattering information will be crucial for experiments studying neutrinos, an important elementary particle that permeates the universe. The PI will mentor a graduate student engaged in this research, and the graduate student will also receive training in the use of state-of-the-art parallel computing resources. The physics of hadron-hadron interactions will be studied using Monte Carlo estimates of path integrals involving quark and gluon fields on a space-time lattice. Nucleon-pion, nucleon-nucleon, and nucleon-hyperon scattering phase shifts will be computed, yielding important information on hadron structure. Scattering processes involving nucleon-pion-pion will also be considered. New computational techniques, such as the stochastic LapH method, have made possible such computations in lattice QCD, which involve estimating temporal correlation matrices of multi-hadron and excited-state operators. Form factors involving the nucleon and transitions through the Delta baryon will be a particular focus since they are crucial to accelerated-based neutrino experiments, such as the Deep Underground Neutrino Experiment (DUNE).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.