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arXiv · 1207.6529

On the role of Collins effect in the single spin asymmetry A_N in p(transv. polarized) p --> h X processes

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

The much debated issue of the transverse single spin asymmetry A_N observed in the inclusive large P_T production of a single hadron in pp interactions, p(transv. polarized) p --> pion X, is considered in a TMD factorization scheme. A previous result [1,2] stating that the maximum contribution of the Collins effect is strongly suppressed, is revisited, correcting a numerical error. New estimates are given, adopting the Collins functions recently extracted from SIDIS and e+e- data, and phenomenological consequences are discussed.

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M. Anselmino, M. Boglione, U. D'Alesio, E. Leader, S. Melis, F. Murgia, A. Prokudin. 2012-07-27. On the role of Collins effect in the single spin asymmetry A_N in p(transv. polarized) p --> h X processes. https://doi.org/10.1103/physrevd.86.074032

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