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arXiv · 1211.7218

Worldline techniques and QCD observables

N. G. Stefanis
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Abstract

This report attempts to capture the essential workings of gauge links (Wilson lines) inside gauge-invariant formulations of parton distribution functions in QCD and gain some deeper insight into their key (renormalization) properties. We show, in particular, that the one-loop anomalous dimension of the Cherednikov-Stefanis quark TMD PDF is in the lightcone gauge $A^+=0$, combined with the Mandelstam--Leibbrandt pole prescription, the same as that obtained in the special covariant gauge $a=-3$, leaving no uncanceled rapidity singularities.

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N. G. Stefanis. 2012-11-30. Worldline techniques and QCD observables. https://arxiv.org/abs/1211.7218

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