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arXiv · 1110.6516

On gauge invariant nucleon spin decomposition

P. M. Zhang·D. G. Pak
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Abstract

A non-uniqueness problem of gauge invariant separation of quark and gluon contributions to nucleon spin is considered. We show that there is a wide number of gauge invariant spin decompositions each of them reduces to the canonical one in a special gauge. A class of physical gauge equivalent nucleon spin decompositions is selected by requirements of consistence with helicity notion described within E(2) little group representation theory and with gluon helicity Δg measured in experiment.

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P. M. Zhang, D. G. Pak. 2012-05-30. On gauge invariant nucleon spin decomposition. https://doi.org/10.1140/epja%2Fi2012-12091-8

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