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arXiv · hep-ph/0411387

Hadron annihilation into two photons and backward dVCS in the scaling regime of QCD

B. Pire·L. Szymanowski
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Abstract

We study the scaling regime of hadron-(anti)-hadron annihilation into a deeply virtual photon and a real photon, H anti-H -> gamma^* gamma, and deep backward virtual Compton scattering, gamma^* H -> H gamma. We advocate that there is a kinematical region where the scattering amplitude factorizes into a short-distance matrix element and a long-distance dominated object: a transition distribution amplitude which describes the hadron to photon transition.

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B. Pire, L. Szymanowski. 2005-05-23. Hadron annihilation into two photons and backward dVCS in the scaling regime of QCD. https://doi.org/10.1103/physrevd.71.111501

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