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arXiv · 2001.06449

On gauge invariance of transverse momentum dependent distributions at small x

Renaud Boussarie·Yacine Mehtar-Tani
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Abstract

The interplay between the small x limit of QCD amplitudes and QCD factorization at moderate x has been studied extensively in recent years. It was finally shown that semiclassical formulations of small x physics can have the form of an infinite twist framework involving Transverse Momentum Dependent (TMD) distributions in the eikonal limit. In this work, we demonstrate that small x distributions can be formulated in terms of transverse gauge links. This allows in particular for direct and efficient decompositions of observables into subamplitudes involving gauge invariant sub-operators which span parton distributions.

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Renaud Boussarie, Yacine Mehtar-Tani. 2020-01-17. On gauge invariance of transverse momentum dependent distributions at small x. https://doi.org/10.1103/physrevd.103.094012

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