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تسجيل مستخدم جديدProcess dependence of the gluon Sivers function in inclusive $pp$ collisions: phenomenology
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Within the so-called color gauge invariant generalized parton model, a TMD scheme including initial- (ISI) and final-state (FSI) interactions, we present a phenomenological analysis of available SSA data for pion and $D$-meson production in $pp$ collisions. This allows us, for the first time, to put a preliminary constraint on the two universal types of gluon Sivers function entering the model. Predictions for SSAs in $J/psi$ and direct photon production, as well as a comparison with the simpler generalized parton model (without ISIs and FSIs), are also presented.
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Within a generalized parton model approach, with inclusion of spin and intrinsic transverse momentum effects, we show how the latest, highly precise, midrapidity data on the transverse single spin asymmetry measured in $pptopi^0, X$ by the PHENIX Col
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