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arXiv · hep-ph/9804337

Quark Orbital-Angular-Momentum Distribution in the Nucleon

Pervez Hoodbhoy·Xiangdong Ji·Wei Lu
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Abstract

We introduce gauge-invariant quark and gluon angular momentum distributions after making a generalization of the angular momentum density operators. From the quark angular momentum distribution, we define the gauge-invariant and leading-twist quark {\it orbital} angular momentum distribution $L_q(x)$. The latter can be extracted from data on the polarized and unpolarized quark distributions and the off-forward distribution $E(x)$ in the forward limit. We comment upon the evolution equations obeyed by this as well as other orbital distributions considered in the literature.

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Pervez Hoodbhoy, Xiangdong Ji, Wei Lu. 1998-08-12. Quark Orbital-Angular-Momentum Distribution in the Nucleon. https://doi.org/10.1103/physrevd.59.014013

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