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Exclusive production of pion pairs in gamma^* gamma collisions at large Q^2

Markus Diehl·Thierry Gousset·Bernard Pire
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Abstract

We perform a QCD analysis of the exclusive production of two mesons in gamma^* gamma collisions in the kinematical domain of large photon virtuality Q and small hadronic invariant mass W. This reaction is dominated by a scale invariant mechanism which factorizes into a perturbative subprocess, gamma^* gamma --> q qbar or gamma^* gamma --> g g, and a generalized two-meson distribution amplitude. We develop in detail the phenomenology of this process at e^+ e^- colliders. Using a simple model for the two-pion distribution amplitude, based on its general properties, we estimate the cross section for the kinematics accessible at BABAR, BELLE, CLEO and LEP.

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Markus Diehl, Thierry Gousset, Bernard Pire. 2000-07-13. Exclusive production of pion pairs in gamma^* gamma collisions at large Q^2. https://doi.org/10.1103/physrevd.62.073014

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