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arXiv · 1612.06413

Study of the sign change of the Sivers function from STAR Collaboration W/Z production data

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

Recent data on the transverse single spin asymmetry $A_N$ measured by the STAR Collaboration for $p^\uparrow \, p \to W^\pm/Z^0 \, X$ reactions at RHIC allow the first investigation of the Sivers function in Drell-Yan processes and of its expected sign change with respect to SIDIS processes. A new extraction of the Sivers functions from the latest SIDIS data is performed and a critical assessment of the significance of the STAR data is attempted.

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M. Anselmino, M. Boglione, U. D'Alesio, F. Murgia, A. Prokudin. 2016-12-19. Study of the sign change of the Sivers function from STAR Collaboration W/Z production data. https://doi.org/10.1007/jhep04(2017)046

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