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arXiv · hep-ph/9912364

The perturbative limit of the two-pion distribution amplitude

M. Diehl·Th. Feldmann·P. Kroll·C. Vogt
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Abstract

We consider pion pair production in two-photon collisions, gamma* gamma -> pi+ pi-, at large photon virtuality Q^2 and center-of-mass energy \sqrt{s} in the hard-scattering picture. In the limit where s is large but s << Q^2 we derive an expression for the two-pion light-cone distribution in terms of the conventional pion distribution amplitudes. Our result reproduces the well-known scaling behavior, helicity selection rule and symmetry relations in this regime.

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M. Diehl, Th. Feldmann, P. Kroll, C. Vogt. 1999-12-15. The perturbative limit of the two-pion distribution amplitude. https://doi.org/10.1103/physrevd.61.074029

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