Transverse Momentum Dependent Distributions from Lattice QCD

格子 QCD 的横向动量相关分布

• 批准号: 445271327
• 负责人: Professor Dr. Andreas Schäfer
• 金额: --
• 依托单位: Institut für Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/445271327?language=en
• 关键词: Transverse; Momentum; Dependent; Distributions; Lattice

QCD describes the quantum mechanical quark-gluon structure of hadrons like the proton. Knowledge of this structure is important as background information if one wants to interpret, e.g., proton-proton collisions at LHC (CERN), but also because QCD allows to study the full breadth of complex properties of non-Abelean local gauge theories. In the beginning, research focused on collinear physics and simple probability distributions. Meanwhile, research focuses on functions which are sensitive to phase correlations. Among these Transverse Momentum Dependent parton distribution functions (TMDPDFs or simply TMDs) are especially interesting. The projected new electron-ion collider (EIC) in the US will allow to study these in unprecedented detail. However, the experimentally accessable information will be insufficient to pin all TMDs down. (A nucleon has eight different TMDs for each quark flavor and each is a function of Bjorken x and transverse momentum, and in addition there are gluon TMDs.) Therefore, the experimental information must be supplemented by Lattice QCD information. This we want continue to do. A few years ago we were the first to formulate the needed techniques and perform numerical studies and today we collaborate with the leading groups in this field. In addition we plan to calculate the flavour separated quark orbital angular momentum and its scale dependence.

QCD 描述了质子等强子的量子力学夸克-胶子结构。如果想要解释大型强子对撞机 (CERN) 的质子-质子碰撞等问题，了解这种结构作为背景信息非常重要，而且还因为 QCD 允许研究非阿贝尔局域规范理论的复杂特性的全部范围。最初，研究重点是共线物理和简单概率分布。同时，研究重点是对相位相关性敏感的函数。在这些横向动量相关部分子分布函数（TMDPDF 或简称 TMD）中特别有趣。预计在美国建造的新型电子离子对撞机（EIC）将能够对这些问题进行前所未有的详细研究。然而，通过实验获得的信息不足以确定所有 TMD。 （核子的每种夸克风味有八种不同的 TMD，每个都是 Bjorken x 和横向动量的函数，此外还有胶子 TMD。）因此，实验信息必须由格子 QCD 信息补充。我们希望继续这样做。几年前，我们率先制定了所需的技术并进行了数值研究，今天我们与该领域的领先团队合作。此外，我们计划计算味分离夸克轨道角动量及其尺度依赖性。