Nonpartonic effects in pion electroproduction in the HERMES kinematical region
نویسندگان
چکیده
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 meson on the extraction of the d̄ − ū asymmetry from charged pion DIS multiplicities. We also show that it is the exclusive-ρ channel which accounts for the experimentally observed effect of the excess of charged over neutral pions produced at large z.
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