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arXiv · 1011.2466

Quark and Gluon Angular Momentum in the Nucleon

Matthias Burkardt·Hikmat BC·Abdullah Jarrah
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Abstract

Parton distributions in impact parameter space, which are obtained by Fourier transforming GPDs, are exhibit a significant deviation from axial symmetry when the target and/or quark is transversely polarized. From this deformation, we present an intuitive derivation of the Ji relation. In a scalar diquark model and in QED, we compare the Ji and Jaffe-Manohar decompositions of the nucleon spin. Using the MIT bag model, we estimate spectator effects through the presence of the gluon vector potential in the definitions of the quark orbital angular momentum.

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Matthias Burkardt, Hikmat BC, Abdullah Jarrah. 2010-11-10. Quark and Gluon Angular Momentum in the Nucleon. https://doi.org/10.1063/1.3647096

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