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arXiv · 1407.2445

Phenomenology of unpolarized TMDs from Semi-Inclusive DIS data

Abstract

We discuss the dependence on the flavor of the intrinsic transverse momentum in unpolarized transverse-momentum-dependent distribution functions (TMD PDFs) and fragmentation functions (TMD FFs) analyzing data of semi-inclusive deep-inelastic scattering (SIDIS) released by the HERMES collaboration. Adopting a flavor-dependent Gaussian model in the transverse momentum and neglecting QCD evolution, we find interesting evidences concerning the flavor dependence in TMD FFs, whereas the indications are weaker in TMD PDFs and deserve further investigations. Inclusions of new data sets of SIDIS, electron-positron annihilations and and Drell-Yan (DY) events require a proper treatment of QCD evolution. We try to get constraints on the non-perturbative Sudakov factor from electron-positron annihilations into hadrons.

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Andrea Signori, Alessandro Bacchetta, Marco Radici. 2014-07-09. Phenomenology of unpolarized TMDs from Semi-Inclusive DIS data. https://arxiv.org/abs/1407.2445

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