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arXiv · hep-ph/9808462

Are Parton Distributions Positive?

Stefano Forte·Guido Altarelli·Giovanni Ridolfi
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Abstract

We show that the naive positivity conditions on polarized parton distributions which follow from their probabilistic interpretation in the naive parton model are reproduced in perturbative QCD at the leading log level if the quark and gluon distribution are defined in terms of physical processes. We show how these conditions are modified at the next-to-leading level, and discuss their phenomenological implications, in particular in view of the determination of the polarized gluon distribution

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Stefano Forte, Guido Altarelli, Giovanni Ridolfi. 1998-08-28. Are Parton Distributions Positive?. https://doi.org/10.1016/s0920-5632(99)00150-4

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