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arXiv · 1203.4392

On timelike and spacelike hard exclusive reactions

D. Mueller·B. Pire·L. Szymanowski·J. Wagner
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Abstract

We show to next-to-leading order accuracy in the strong coupling alpha_s how the collinear factorization properties of QCD in the generalized Bjorken regime relate exclusive amplitudes for spacelike and timelike hadronic processes. This yields simple space--to--timelike relations linking the amplitudes for electroproduction of a photon or meson to those for photo- or meso-production of a lepton pair. These relations constitute a new test of the relevance of leading twist analyzes of experimental data.

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D. Mueller, B. Pire, L. Szymanowski, J. Wagner. 2012-03-20. On timelike and spacelike hard exclusive reactions. https://doi.org/10.1103/physrevd.86.031502

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