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arXiv · 0711.3192

Sum rule for the double virtual Compton scattering

E. A. Kuraev·S. Bakmaev·E. Tomasi-Gustafsson·V. V. Bytev
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Abstract

The two photon exchange amplitude is investigated in frame of analytic properties of the virtual Compton scattering amplitude as a function of the invariant mass squared of the intermediate hadronic state. A sum rule is built, based on arguments from analyticity. It relates the differential cross section of elastic electron-proton scattering including form factors, and the cross section of inelastic scattering channel, with a contribution of nucleon anti-nucleon pair production arising from the Fermi statistics. The last term is calculated in frame of a simple model of nucleon-pion interaction.

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E. A. Kuraev, S. Bakmaev, E. Tomasi-Gustafsson, V. V. Bytev. 2007-11-20. Sum rule for the double virtual Compton scattering. https://arxiv.org/abs/0711.3192

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