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arXiv · 1012.3565

New insight on the Sivers transverse momentum dependent distribution function

M. Anselmino·M. Boglione·U. D'Alesio·S. Melis·F. Murgia·A. Prokudin
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Abstract

Polarised Semi-Inclusive Deep Inelastic Scattering (SIDIS) processes allow to study Transverse Momentum Dependent partonic distributions (TMDs), which reveal a non trivial three dimensional internal structure of the hadrons in momentum space. One of the most representative of the TMDs is the so-called Sivers function that describes the distribution of unpolarized quarks inside a transversely polarized proton. We present a novel extraction of the Sivers distribution functions from the most recent experimental data of HERMES and COMPASS experiments. Using suitable parametrizations, within the TMD factorization scheme, and a simple fitting strategy, we also perform a preliminary exploration of the role of the proton sea quarks.

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M. Anselmino, M. Boglione, U. D'Alesio, S. Melis, F. Murgia, A. Prokudin. 2010-12-17. New insight on the Sivers transverse momentum dependent distribution function. https://doi.org/10.1088/1742-6596%2F295%2F1%2F012062

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