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arXiv · 1211.1947

Soft and Collinear Factorization and Transverse Momentum Dependent Parton Distribution Functions

Miguel G. Echevarria·Ahmad Idilbi·Ignazio Scimemi
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Abstract

In this work we consider how a parton distribution function, with an explicit transverse momentum dependence can be properly defined in a regularization-scheme independent manner. We argue that by considering a factorized form of the transverse momentum dependent spectrum for the production of a heavy lepton pair in Drell-Yan reaction, one should first split the relevant soft function into two boost invariant contributions. When those soft contributions are added to the pure collinear contributions, well-defined hadronic matrix elements emerge, i.e., the transverse momentum dependent distributions. We also perform a comparison with Collins' definition.

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Miguel G. Echevarria, Ahmad Idilbi, Ignazio Scimemi. 2013-09-05. Soft and Collinear Factorization and Transverse Momentum Dependent Parton Distribution Functions. https://doi.org/10.1016/j.physletb.2013.09.003

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