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Genuine twist-3 contributions to the generalized parton distributions from instantons

D. V. Kiptily·M. V. Polyakov
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Abstract

The genuine twist-3 quark-gluon contributions to the Generalized Parton Distributions (GPDs) are estimated in the model of the instanton vacuum. These twist-3 effects are found to be parametrically suppressed relative to the ``kinematical'' twist-3 ones due to the small packing fraction of the instanton vacuum. We derive exact sum rules for the twist-3 GPDs.

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D. V. Kiptily, M. V. Polyakov. 2003-02-14. Genuine twist-3 contributions to the generalized parton distributions from instantons. https://arxiv.org/abs/hep-ph/0212372

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