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

构成原子核的质子和中子是由夸克和胶子这两种基本粒子组成的，它们之间的相互作用可以用量子色动力学（QCD）来描述。这一理论表明，许多其他类型的复合粒子，如强子，应该以不稳定共振的形式存在于自然界中。QCD预测的某些强子共振性质将利用大规模的计算资源进行研究。拟议的研究为当前的实验提供了支持，例如在托马斯杰斐逊国家加速器设施（JLab）的D厅进行的GlueX实验。核子的结构和散射涉及到一个特殊的强子被称为德尔塔重子将是另一个焦点。这种散射信息对于研究中微子的实验至关重要，中微子是一种渗透宇宙的重要基本粒子。PI将指导一名从事这项研究的研究生，该研究生也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被研究使用蒙特卡洛估计路径积分涉及时空晶格上的夸克和胶子场。核子-介子、核子-核子和核子-超子散射相移将被计算，得到强子结构的重要信息。涉及核子-介子-介子的散射过程也将被考虑。新的计算技术，如随机LapH方法，使得这种计算在晶格QCD中成为可能，它涉及估计多强子和激发态算子的时间相关矩阵。涉及核子和δ重子跃迁的形状因素将成为特别关注的焦点，因为它们对基于加速的中微子实验至关重要，例如深地下中微子实验（DUNE）。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.