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arXiv · 0804.0422

Global Analysis of Helicity Parton Densities and Their Uncertainties

Daniel de Florian·Rodolfo Sassot·Marco Stratmann·Werner Vogelsang
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Abstract

We present a new analysis of the helicity parton distributions of the nucleon. The analysis takes into account the available data from inclusive and semi-inclusive polarized deep inelastic scattering, as well as from polarized pp scattering at RHIC. For the first time, all theoretical calculations are performed fully at next-to-leading order (NLO) of perturbative QCD, using a method that allows to incorporate the NLO corrections in a very fast and efficient way in the analysis. We find evidence for a rather small gluon polarization in the nucleon, over a limited region of momentum fraction, and for interesting flavor patterns in the polarized sea.

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Daniel de Florian, Rodolfo Sassot, Marco Stratmann, Werner Vogelsang. 2008-04-02. Global Analysis of Helicity Parton Densities and Their Uncertainties. https://doi.org/10.1103/physrevlett.101.072001

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