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arXiv · 1406.5539

A first unbiased global determination of polarized PDFs and their uncertainties

Emanuele R. Nocera·Richard D. Ball·Stefano Forte·Giovanni Ridolfi·Juan Rojo
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Abstract

We present a first global determination of spin-dependent parton distribution functions (PDFs) and their uncertainties using the NNPDF methodology: NNPDFpol1.1. Longitudinally polarized deep-inelastic scattering data, already used for the previous NNPDFpol1.0 PDF set, are supplemented with the most recent polarized hadron collider data for inclusive jet and $W$ boson production from the STAR and PHENIX experiments at RHIC, and with open-charm production data from the COMPASS experiment, thereby allowing for a separate determination of the polarized quark and anti-quark PDFs, and an improved determination of the medium- and large-$x$ polarized gluon PDF. We study the phenomenological implications of the NNPDFpol1.1 set, and we provide predictions for the longitudinal double-spin asymmetry for semi-inclusive pion production at RHIC.

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Emanuele R. Nocera, Richard D. Ball, Stefano Forte, Giovanni Ridolfi, Juan Rojo. 2014-09-01. A first unbiased global determination of polarized PDFs and their uncertainties. https://doi.org/10.1016/j.nuclphysb.2014.08.008

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