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arXiv · 1908.07312

The gluon Sivers function and its process dependence from RHIC data

Cristian Pisano·Umberto D'Alesio·Carlo Flore·Francesco Murgia·Pieter Taels
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Abstract

We present a phenomenological analysis of available data on single spin asymmetries for pion and $D$ meson production in proton-proton collisions at RHIC within the color gauge invariant generalized parton model (CGI-GPM), which includes initial (ISIs) and final (FSIs) state interactions in a transverse momentum dependent formalism. This study allows us, for the first time, to put preliminary constraints on the two independent gluon Sivers functions entering the model. We also present a comparison with the simpler generalized parton model (without ISIs and FSIs).

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Cristian Pisano, Umberto D'Alesio, Carlo Flore, Francesco Murgia, Pieter Taels. 2019-08-20. The gluon Sivers function and its process dependence from RHIC data. https://arxiv.org/abs/1908.07312

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