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Higher-twist contributions to F_L and F_2 from instantons

B. Dressler·M. Maul·C. Weiss
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Abstract

We study the twist-4 contribution to the unpolarized nucleon structure functions, F_L and F_2, in an approach where the vacuum structure of QCD is described by a dilute medium of instantons ($\barρ/ \bar R \ll 1$). The dominant power corrections come from the twist-4 quark-gluon operators and are of the order $1/(\barρ^2 Q^2)$. The contributions from four-quark operators are suppressed. The approach predicts large 1/Q^2-corrections to F_L, in agreement with the results of QCD fits to the data.

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B. Dressler, M. Maul, C. Weiss. 2000-06-21. Higher-twist contributions to F_L and F_2 from instantons. https://arxiv.org/abs/hep-ph/0006252

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