Extensive experimental measurements of spin and azimuthal asymmetries in various processes have stimulated theoretical interest and progress in the studies of the nucleon structure. The interpretation of experimental data in terms of parton distribution functions, generalized to describe transverse momentum and spatial parton distributions, is one of the main remaining challenges of modern nuclear physics. These new parton distribution and fragmentation functions encode the motion and the position of partons and are often referred to as three-dimensional distributions describing the three-dimensional (3D) structure of the nucleon. Understanding of the production mechanism and performing phenomenological studies compatible with factorization theorems using minimal model assumptions are goals of the analysis of the experimental data. HERMES and COMPASS Collaborations and experiments at Jefferson Lab have collected a wealth of polarized and unpolarized Semi-Inclusive Deep Inelastic Scattering (SIDIS) data. These data play a crucial role in current understanding of nucleon spin phenomena as they cover a broad kinematical range. The Jefferson Lab 12 GeV upgrade data on polarized and unpolarized SIDIS will have a remarkably higher precision at large parton fractional momentum x compared to the existing data. We argue that both experimental and phenomenological communities will benefit from the development of a comprehensive extraction framework that will facilitate the extraction of the 3D nucleon structure, help understand various assumptions in extraction and data analysis, help to insure the model independence of the experimental data and validate the extracted functions. In this review we present the latest developments in the field of the spin asymmetries with emphasis on observables beyond the leading twist in SIDIS, indispensable for studies of the complex 3D nucleon structure, and discuss different components involved in precision extraction of the 3D partonic distribution and fragmentation functions.

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自旋轨道的相关性和核子的结构

各种过程中自旋和方位角不对称性的广泛实验测量激发了核子结构研究的理论兴趣和进展。用Parton分布函数来解释实验数据，概括地描述横向动量和空间Parton分布，是现代核物理面临的主要挑战之一。这些新的parton分布和片段化功能编码parton的运动和位置，通常被称为描述核子的三维（3D）结构的三维分布。了解生产机理并使用最小的模型假设进行与因式分解定理兼容的现象学研究是实验数据分析的目标。HERMES和COMPASS Jefferson实验室的合作和实验收集了许多极化和非极化的半包容性深非弹性散射（SIDIS）数据。由于这些数据涵盖了广泛的运动学范围，因此它们在当前对核子自旋现象的理解中起着至关重要的作用。极化和非极化SIDIS上的Jefferson Lab 12 GeV升级数据在很大的部分动量下将具有非常高的精度x与现有数据相比。我们认为，实验和现象学共同体都将受益于全面提取框架的开发，该框架将促进3D核子结构的提取，有助于理解提取和数据分析中的各种假设，有助于确保实验数据的模型独立性和验证提取的功能。在这篇综述中，我们介绍了自旋不对称性领域的最新进展，重点是SIDIS中领先的扭转以外的可观测物，这对于研究复杂的3D核子结构必不可少，并讨论了涉及3D部分子分布的精确提取的不同成分以及碎片功能。