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arXiv · 1304.7691

Sivers effect and the single spin asymmetry A_N in p(transv. pol.) p --> h X processes

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

The single spin asymmetry A_N, for large P_T single inclusive particle production in p(transv. pol.) p collisions, is considered within a generalised parton model and a transverse momentum dependent factorisation scheme. The focus is on the Sivers effect and the study of its potential contribution to A_N, based on a careful analysis of the Sivers functions extracted from azimuthal asymmetries in semi-inclusive deep inelastic scattering processes. It is found that such Sivers functions could explain most features of the A_N data, including some recent STAR results which show the persistence of a non zero A_N up to surprisingly large P_T values.

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M. Anselmino, M. Boglione, U. D'Alesio, S. Melis, F. Murgia, A. Prokudin. 2013-09-26. Sivers effect and the single spin asymmetry A_N in p(transv. pol.) p --> h X processes. https://doi.org/10.1103/physrevd.88.054023

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