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arXiv · 1209.3892

Definition and Evolution of Transverse Momentum Distributions

Miguel G. Echevarria·Ahmad Idilbi·Ignazio Scimemi
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Abstract

We consider the definition of unpolarized transverse-momentum-dependent parton distribution functions while staying on-the-light-cone. By imposing a requirement of identical treatment of two collinear sectors, our approach, compatible with a generic factorization theorem with the soft function included, is valid for all non-ultra-violet regulators (as it should), an issue which causes much confusion in the whole field. We explain how large logarithms can be resummed in a way which can be considered as an alternative to the use of Collins-Soper evolution equation. The evolution properties are also discussed and the gauge-invariance, in both classes of gauges, regular and singular, is emphasized.

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Miguel G. Echevarria, Ahmad Idilbi, Ignazio Scimemi. 2012-09-18. Definition and Evolution of Transverse Momentum Distributions. https://doi.org/10.1142/s2010194512009130

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