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arXiv · 1701.01148

Transverse single-spin asymmetries in $\ell \,p^\uparrow \to h \,X$ within a TMD approach: Role of quasireal photon exchange

Umberto D'Alesio·Carlo Flore·Francesco Murgia
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Abstract

We present an updated study of transverse single-spin asymmetries for the inclusive large-$P_T$ processes $\ell \, p^\uparrow \to h\, X$ and $\ell\, p^\uparrow \to {\rm jet}\,X$, within a transverse momentum-dependent approach, including the contribution of quasireal (Weizs\"acker-Williams) photons. In the spirit of a unified transverse momentum-dependent scheme, predictions are obtained adopting the Sivers and transversity distributions and the Collins fragmentation functions as extracted from fits to the azimuthal asymmetries measured in semi-inclusive deep inelastic scattering and $e^+e^-$ annihilation processes. The description of the available data is extremely good, showing a clear general improvement with respect to the previous leading-order analysis. Predictions for unpolarized cross sections and single-spin asymmetries for ongoing and future experiments are also given.

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Umberto D'Alesio, Carlo Flore, Francesco Murgia. 2017-01-04. Transverse single-spin asymmetries in $\ell \,p^\uparrow \to h \,X$ within a TMD approach: Role of quasireal photon exchange. https://doi.org/10.1103/physrevd.95.094002

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