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arXiv · 0709.1284

Spin and orbital angular momentum in gauge theories (II): QCD and nucleon spin structure

X. S. Chen·X. F. Lü·W. M. Sun·F. Wang·T. Goldman
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Abstract

Parallel to the construction of gauge invariant spin and orbital angular momentum for QED in paper (I) of this series, we present here an analogous but non-trivial solution for QCD. Explicitly gauge invariant spin and orbital angular momentum operators of quarks and gluons are obtained. This was previously thought to be an impossible task, and opens a more promising avenue towards the understanding of the nucleon spin structure.

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X. S. Chen, X. F. Lü, W. M. Sun, F. Wang, T. Goldman. 2007-09-09. Spin and orbital angular momentum in gauge theories (II): QCD and nucleon spin structure. https://doi.org/10.1103/physrevlett.100.232002

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