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Nonpartonic effects in pion electroproduction in the HERMES kinematical region

V. Uleshchenko·A. Szczurek
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Abstract

The presentation is concerned with higher twist corrections of nonpartonic origin to semi-inclusive observables in the kinematical region relevant for the HERMES experiment. We demonstrate a strong impact of the VDM-like interaction and the exclusive production of $ρ^0$ meson on the extraction of the $\bar d - \bar u$ asymmetry from charged pion DIS multiplicities. We also show that it is the exclusive-$ρ^0$ channel which accounts for the experimentally observed effect of the excess of charged over neutral pions produced at large $z$.

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V. Uleshchenko, A. Szczurek. 2002-07-03. Nonpartonic effects in pion electroproduction in the HERMES kinematical region. https://arxiv.org/abs/hep-ph/0207049

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