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arXiv · hep-ph/0311015

A rigorous bound on quark distributions in the nucleon

E. Di Salvo
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Abstract

I deduce an inequality between the helicity and the transversity distribution of a quark in a nucleon, at small energy scales. Then I establish, thanks to the positivity constraint, a rigorous bound on longitudinally polarized valence quark densities, which finds nontrivial applications to d-quarks. This, in turn, implies a bound for the distributions of the longitudinally polarized sea, which is probably not SU(3)-symmetric. Some model predictions and parametrizations of quark distributions are examined in the light of these results.

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E. Di Salvo. 2003-11-03. A rigorous bound on quark distributions in the nucleon. https://doi.org/10.1016/j.nuclphysbps.2004.04.140

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