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arXiv · hep-ph/9403251

Anomalous Evolution of Nonsinglet Nucleon Structure Functions

R. D. Ball·V. Barone·S. Forte·M. Genovese
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Abstract

We calculate the scale dependence of nonsinglet nucleon structure functions. Due to anomalous axial symmetry breaking a large flavour asymmetry of the quark--antiquark sea is generated nonperturbatively. This produces a strong scale dependence of the nonsinglet structure function in an intermediate range of $Q^2$. Evolving nonperturbatively a pure valence distribution from an infrared scale we can thus compute $F_2^p-F_2^n$ as measured by the NMC, and give detailed predictions for its $Q^2$ dependence at fixed $x$. We also compare our results with Drell--Yan data.

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R. D. Ball, V. Barone, S. Forte, M. Genovese. 1994-03-09. Anomalous Evolution of Nonsinglet Nucleon Structure Functions. https://doi.org/10.1016/0370-2693(94)91096-0

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