Color Lorentz force on a transversely polarized quark in the nucleon
Abstract
The x2 moment of the genuine twist-3 component of the unpolarized scalar parton distribution function e(x) is related to the average transverse color Lorentz force experienced by a transversely polarized quark in an unpolarized nucleon. This higher-twist quantity probes quark--gluon correlations and provides unique insight into the nonperturbative dynamics of quantum chromodynamics. For the first time, we study the corresponding off-forward matrix element and derive its Lorentz-covariant decomposition in terms of generalized form factors. We calculate these form factors from light-front wave functions obtained by solving the light-front Hamiltonian eigenvalue problem within the Basis Light-Front Quantization framework. Their Fourier transforms provide a spatial picture of the transverse color forces in impact-parameter space. In particular, ℱ2, whose forward limit is directly related to the twist-3 matrix element e2, can be interpreted as the impact-parameter-space representation of the Boer--Mulders force, providing an intuitive spatial picture of the final-state interaction mechanism underlying the Boer--Mulders effect.
Related
- Gluonic nucleon energy correlators and fracture functions for Color Glass Condensate
- Third moments of nucleon unpolarized, polarized, and transversity parton distribution functions from physical-point lattice QCD
- Generalized parton distributions of the nucleon in the chiral quark soliton model II: Chiral anomaly mediation in the polarized GPDs
- Closed-form dyadic Green functions for transversely uniaxial bianisotropic medium with equal magnetoelectric scalars
- Electromagnetic Field of an Oscillating Point Charge Measured by a Transversely Comoving Observer
BibTeX
@misc{zhang2026color,
title = {{Color Lorentz force on a transversely polarized quark in the nucleon}},
author = {Ziqi Zhang and Chandan Mondal and Siqi Xu and Xingbo Zhao and James P. Vary},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.18063},
eprint = {2610.18063},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.18063},
}
RIS
TY - UNPB
TI - Color Lorentz force on a transversely polarized quark in the nucleon
AU - Ziqi Zhang
AU - Chandan Mondal
AU - Siqi Xu
AU - Xingbo Zhao
AU - James P. Vary
PY - 2026
DA - 2026/10/13
PB - arXiv
DO - 10.48550/arxiv.2610.18063
UR - https://arxiv.org/abs/2610.18063
AB - The x^2 moment of the genuine twist-3 component of the unpolarized scalar parton distribution function e(x) is related to the average transverse color Lorentz force experienced by a transversely polarized quark in an unpolarized nucleon. This higher-twist quantity probes quark--gluon correlations and provides unique insight into the nonperturbative dynamics of quantum chromodynamics. For the first time, we study the corresponding off-forward matrix element and derive its Lorentz-covariant decomposition in terms of generalized form factors. We calculate these form factors from light-front wave functions obtained by solving the light-front Hamiltonian eigenvalue problem within the Basis Light-Front Quantization framework. Their Fourier transforms provide a spatial picture of the transverse color forces in impact-parameter space. In particular, ℱ_2, whose forward limit is directly related to the twist-3 matrix element e_2, can be interpreted as the impact-parameter-space representation of the Boer--Mulders force, providing an intuitive spatial picture of the final-state interaction mechanism underlying the Boer--Mulders effect.
ER -