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arXiv · 1403.5226

Twist-2 Generalized TMDs and the Spin/Orbital Structure of the Nucleon

K. Kanazawa·C. Lorcé·A. Metz·B. Pasquini·M. Schlegel
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Abstract

Generalized transverse-momentum dependent parton distributions (GTMDs) encode the most general parton structure of hadrons. Here we focus on two twist-2 GTMDs which are denoted by $F_{1,4}$ and $G_{1,1}$ in parts of the literature. As already shown previously, both GTMDs have a close relation to orbital angular momentum of partons inside a hadron. However, recently even the mere existence of $F_{1,4}$ and $G_{1,1}$ has been doubted. We explain why this claim does not hold. We support our model-independent considerations by calculating the two GTMDs in the scalar diquark model and in the quark-target model, where we also explicitly check the relation to orbital angular momentum. In addition, we compute $F_{1,4}$ and $G_{1,1}$ at large transverse momentum in perturbative Quantum Chromodynamics and show that they are nonzero.

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K. Kanazawa, C. Lorcé, A. Metz, B. Pasquini, M. Schlegel. 2014-07-01. Twist-2 Generalized TMDs and the Spin/Orbital Structure of the Nucleon. https://doi.org/10.1103/physrevd.90.014028

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