Parton Transverse Momentum and Orbital Angular Momentum Distributions

Abstract

The quark orbital angular momentum component of proton spin, $L_q$, can be defined in QCD as the integral of a Wigner phase space distribution weighting the cross product of the quark's transverse position and momentum. It can also be independently defined from the operator product expansion for the off-forward Compton amplitude in terms of a twist-three generalized parton distribution. We provide an explicit link between the two definitions, connecting them through their dependence on partonic intrinsic transverse momentum. Connecting the definitions provides the key for correlating direct experimental determinations of $L_q$, and evaluations through Lattice QCD calculations. The direct observation of quark orbital angular momentum does not require transverse spin polarization, but can occur using longitudinally polarized targets.

5 pages, 2 figures

References in corpus (3)

• Generalized parton correlation functions for a spin-1/2 hadron
• Quark Wigner Distributions and Orbital Angular Momentum
• Flavor decomposition of the elastic nucleon electromagnetic form factors

Cited by in corpus (24)

• Parton distributions and lattice QCD calculations: toward 3D structure
• The Spin Structure of the Nucleon
• Gluon orbital angular momentum at small-$x$
• Generalized TMDs and the exclusive double Drell-Yan process
• Wigner, Husimi and GTMD distributions in the Color Glass Condensate
• Extraction of Generalized Parton Distribution Observables from Deeply Virtual Electron Proton Scattering Experiments
• One-loop renormalization of staple-shaped operators in continuum and lattice regularizations
• Quark orbital dynamics in the proton from Lattice QCD -- from Ji to Jaffe-Manohar orbital angular momentum
• Quark Wigner Distributions Using Light-Front Wave Functions
• Twist-3 GPDs in Deeply-Virtual Compton Scattering
• Lorentz Invariance and QCD Equation of Motion Relations for Generalized Parton Distributions and the Dynamical Origin of Proton Orbital Angular Momentum
• Novel twist-three transverse-spin sum rule for the proton and related generalized parton distributions
• From Ji to Jaffe-Manohar orbital angular momentum in Lattice QCD using a direct derivative method
• Twist-three cross-sections in deeply virtual Compton scattering
• Probing Nucleons and Nuclei in High Energy Collisions
• On the small-$x$ behavior of the orbital angular momentum distributions in QCD
• Exploring twist-4 chiral-even GPDs in the light-front quark-diquark model
• Quark Orbital Angular Momentum in the MIT Bag Model
• Quark spin-orbit correlations in spin-0 and spin-1 mesons using the light-front quark model
• Unraveling sub-leading twist GTMDs of proton using LFQDM
• Twist-4 proton GTMDs in the light-front quark-diquark model
• Spectroscopy of excited quarkonium states in the light-front quark model
• Deciphering Twist-3 Chiral-Even GPDs in the Light-Front Quark-Diquark Model
• Wigner distributions of quarks for different polarizations