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arXiv · hep-ph/9806390

Two-pion light-cone distribution amplitudes from the instanton vacuum

M. V. Polyakov·C. Weiss
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Abstract

We calculate the two-pion light-cone distribution amplitudes in the effective low-energy theory based on the instanton vacuum. These generalized distribution amplitudes describe the soft (non-perturbative) part of the process $γ^*γ\to ππ$ in the region where the c.m. energy is much smaller than the photon virtuality. They can also be used in the analysis of exclusive processes such as $γ^* p \to p + 2π, 3π$ etc.

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M. V. Polyakov, C. Weiss. 1998-06-16. Two-pion light-cone distribution amplitudes from the instanton vacuum. https://doi.org/10.1103/physrevd.59.091502

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