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arXiv · 0903.4797

On the description of exclusive processes beyond the leading twist approximation

I. V. Anikin·D. Yu. Ivanov·B. Pire·L. Szymanowski·S. Wallon
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Abstract

We describe hard exclusive processes beyond the leading twist approximation in a framework based on the Taylor expansion of the amplitude around the dominant light-cone directions. This naturally introduces an appropriate set of non-perturbative correlators whose number is minimalized after taking into account QCD equations of motion and the invariance under rotation on the light-cone. We examplify this method at the twist 3 level and show that the coordinate and momentum space descriptions are fully equivalent.

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I. V. Anikin, D. Yu. Ivanov, B. Pire, L. Szymanowski, S. Wallon. 2009-11-17. On the description of exclusive processes beyond the leading twist approximation. https://doi.org/10.1016/j.physletb.2009.11.040

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