RUI: The 3D Momentum and Spin Structure of the Nucleon in QCD

RUI：QCD 中核子的 3D 动量和自旋结构

• 批准号: 2310031
• 负责人: Alexey Prokudin
• 金额: $ 21.3万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2310031&HistoricalAwards=false
• 关键词: RUI; 3D; Momentum; Spin; Structure

The visible universe is made up of nucleons (protons and neutrons) and electrons. Nucleons themselves are interacting dynamical systems of partons, quarks, and gluons—the degrees of freedom of the theory of strong interactions, Quantum Chromo Dynamics (QCD). Unfolding the QCD quark and gluon structure of nucleons is a crucial area of study in modern nuclear physics. The main objective of this project is to advance theoretical and phenomenological studies of the three-dimensional (3D) momentum and spin structure of the nucleon in QCD. By doing this, the project aims to discover the internal landscape of the nucleon. This project expands the impact of the future program at the Electron-Ion Collider (EIC), a powerful new facility to be built in the United States, as well as of the existing programs at Jefferson Lab and Brookhaven National Laboratory, by performing phenomenological and theoretical studies, providing analysis, explanation of present data, and predictions for future measurements. The project contributes to the education of a diverse, globally engaged workforce with world-class skills by providing and developing courses on modern statistics and nuclear physics, organizing and teaching summer schools for graduate students, and running annual workshops on the 3D structure of the nucleon. The main objective of this project is to advance the theoretical and phenomenological studies of the 3D momentum and spin structure of the nucleon, and to map its internal landscape encoded in the Transverse Momentum Dependent parton distribution and fragmentation functions (TMDs). TMDs are crucial in understanding the correlations between the intrinsic motion and spin of partons and the nucleon, which generate Spin Asymmetries measured in various scattering processes. The project aims to extract the unpolarized 3D structure of the nucleon with high perturbative precision by performing a global QCD analysis of data from experiments from world facilities, including HERMES (DESY), COMPASS (CERN), Jefferson Lab, BELLE (KEK), BaBar (SLAC), BESIII (Beijing), RHIC (BNL), and LHC (CERN). The study involves a global QCD analysis of the data, unifying collinear and TMD physics. The project also focuses on studying the spin structure of the nucleon using all available world data, and extracting polarized TMDs such as Sivers functions, transversity, Collins Fragmentation Functions, and others. In addition, the project will combine TMD-related measurements and the polarized proton-proton scattering data from the Relativistic Heavy Ion Collider (RHIC, BNL) related to twist-3 factorization.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.

可见的宇宙由核（质子和中子）和电子产品组成。核子本身是零件，夸克和麸质的动态系统 - 强相互作用理论的自由度，量子Chromo动力学（QCD）。展开核的QCD夸克和麸质结构是现代核物理学研究的关键领域。该项目的主要目的是推进QCD中核子的三维（3D）动量和自旋结构的理论和现象学研究。通过这样做，该项目旨在发现核子的内部景观。该项目扩大了在美国建立的强大新设施的电子离子对撞机（EIC）以及杰斐逊实验室和布鲁克黑文国家实验室的现有计划，通过执行现象学和理论研究，提供分析，解释当前数据以及未来测量的预测，以扩大了未来计划的影响。该项目通过提供和开发有关现代统计和核物理学的课程，为研究生组织和教授暑期学校，并在核的3D结构上举办年度研讨会，从而有助于对多样性，全球订婚的劳动力的教育。该项目的主要目的是推进核的3D动量和自旋结构的理论和现象学研究，并绘制其内部景观，该景观在横向动量依赖的Parton分布和碎片函数（TMDS）中编码。 TMD对于理解零件的固有运动与核的自旋与核的相关性至关重要，而核的固有运动与核的自旋之间产生了在各种散射过程中测得的自旋不对称。该项目旨在通过对来自世界设施的实验的数据进行全球QCD分析，包括爱马仕（Desy），Compass（Cers）（Cern），Jefferson Lab，Belle（Kek），Babar（Babar（Slac），Babar（Slac），Besiii（besiii（besiii（beijing），rhic（rhic），Rhic（Bnl）和LHC（CERN）），该项目旨在以高扰动精度提取核的未脱光化3D结构。该研究涉及对数据的全局QCD分析，统一共线和TMD物理。该项目还专注于使用所有可用的世界数据研究核子的自旋结构，并提取偏振型TMD，例如Sivers功能，横向性，Collins片段化功能等。此外，该项目将结合与TMD相关的测量结果和与Twist-3因化有关的相对论重离子对撞机（RHIC，BNL）的极化质子 - 蛋白散射数据。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识率和广泛影响来评估的支持，并被认为是珍贵的支持。