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Extracting the Sivers function from polarized SIDIS data and making predictions

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

The most recent data on the weighted transverse single spin asymmetry $A_{UT}^{\sin(ϕ_h-ϕ_S)}$ from HERMES and COMPASS collaborations are analysed within LO parton model with unintegrated parton distribution and fragmentation functions; all transverse motions are taken into account, with exact kinematics, in the elementary interactions. The overall quality of the data is such that, for the first time, a rather well constrained extraction of the Sivers function for $u$ and $d$ quarks is possible and is performed. Comparisons with models are made. Based on the extracted Sivers functions, predictions for $A_{UT}^{\sin(ϕ_h-ϕ_S)}$ asymmetries at JLab are given; suggestions for further measurements at COMPASS, with a transversely polarized hydrogen target and selecting favourable kinematical ranges, are discussed. Predictions are also presented for Single Spin Asymmetries (SSA) in Drell-Yan processes at RHIC and GSI.

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M. Anselmino, M. Boglione, U. D'Alesio, A. Kotzinian, F. Murgia, A. Prokudin. 2005-11-21. Extracting the Sivers function from polarized SIDIS data and making predictions. https://doi.org/10.1103/physrevd.72.094007%2010.1103%2Fphysrevd.72.099903

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