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arXiv · hep-ph/0412316

Comments on Cahn and Sivers effects in SIDIS

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

The role of intrinsic $k_\perp$ in semi-inclusive Deep Inelastic Scattering (SIDIS) processes ($\ell p \to \ell h X$) is studied within QCD parton model at leading order. The resulting picture is applied to the description of the weighted single spin asymmetry $A_{UL}^{\sinϕ_h}$ measured by HERMES. It is shown that these data could be described by the Sivers mechanism alone. However, the extracted Sivers functions fail to describe the HERMES data on $A_{UT}^{\sin(ϕ_h-ϕ_S)}$.

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M. Anselmino, M. Boglione, U. D'Alesio, A. Kotzinian, F. Murgia, A. Prokudin. 2004-12-21. Comments on Cahn and Sivers effects in SIDIS. https://doi.org/10.1142/9789812701909_0072

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