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arXiv · 1503.03518

Achievements and open issues in the determination of polarized parton distribution functions

Emanuele R. Nocera
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Abstract

I review the current status of the determination of helicity-dependent, or polarized, parton distribution functions from a comprehensive analysis of experimental data in perturbative quantum chromodynamics. I illustrate the latest achievements driven by new measurements in polarized proton-proton collisions at the Relativistic Heavy Ion Collider, namely the first evidence of a sizable polarized light sea quark asymmetry and of a positive polarized gluon distribution in the proton. I discuss which are the open issues in the determination of polarized distributions, and how these may be addressed in the future by ongoing, planned and proposed experimental programs.

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Emanuele R. Nocera. 2015-03-11. Achievements and open issues in the determination of polarized parton distribution functions. https://doi.org/10.1142/s2010194516600168

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