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arXiv · hep-ph/9802346

Gauge invariance and hadron structure

Xiang-Song Chen·Fan Wang
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Abstract

We prove that the {\em gauge dependent} gluon spin, gluon and quark orbital angular momenta operators have {\em gauge invariant} expectation values on hadron states with {\em definite} momentum and polarization, therefore the conventional decomposition of nucleon spin into contributions from the spin and orbital angular momentum of quark and gluon is {\em gauge independent}. Similar conclusions apply to the {\em gauge dependent} quark momentum and kinetic energy operators, and accordingly nucleon momentum and mass structures.

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Xiang-Song Chen, Fan Wang. 1998-09-19. Gauge invariance and hadron structure. https://arxiv.org/abs/hep-ph/9802346

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