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arXiv · hep-ph/9409249

Anomalous Evolution of Nonsinglet Structure Functions

Stefano Forte·Richard D. Ball
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Abstract

We review a formalism that includes the effects of nonperturbative U(1) symmetry breaking on the QCD evolution of nonsinglet structure functions. We show that a strong scale dependence is generated in an intermediate energy range $0.5 \lsim Q^2 \lsim 5$~GeV$^2$ for all values of $x$. We show that this explains naturally the observed violation of the Gottfried sum, and allows a determination of the shape of the nonsinglet structure function, in excellent agreement with experiment. We argue that these effects may affect the determination of $α_s$ from deep--inelastic scattering.

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Stefano Forte, Richard D. Ball. 1994-09-30. Anomalous Evolution of Nonsinglet Structure Functions. https://doi.org/10.1016/0920-5632(95)00037-a

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