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arXiv · hep-ph/0102036

Spin structure in non-forward partons

Steven D. Bass
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Abstract

Renormalisation induces anomalous contributions in light-cone correlation functions. We discuss the role of the axial anomaly and gluon topology in non-forward parton distributions noting that non-forward matrix elements of the gluonic Chern-Simons current K_μ are not gauge-invariant even in perturbation theory. The axial anomaly means that one has to be careful how to interpret information from hard exclusive reactions about the orbital angular-momentum carried by the proton's internal constituents.

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Steven D. Bass. 2001-02-04. Spin structure in non-forward partons. https://doi.org/10.1103/physrevd.65.074025

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