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arXiv · hep-ph/9603249

Gauge-Invariant Decomposition of Nucleon Spin and Its Spin-Off

Xiangdong Ji
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Abstract

I introduce a gauge invariant decomposition of the nucleon spin into quark helicity, quark orbital, and gluon contributions. The total quark (and hence the quark orbital) contribution is shown to be measurable through virtual Compton scattering in a special kinematic region where single quark scattering dominates. This deeply-virtual Compton scattering (DVCS) has much potential to unravel the quark and gluon structure of the nucleon.

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Xiangdong Ji. 1996-03-08. Gauge-Invariant Decomposition of Nucleon Spin and Its Spin-Off. https://doi.org/10.1103/physrevlett.78.610

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