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Dispersion relation formalism for virtual Compton scattering and the generalized polarizabilities of the nucleon

B. Pasquini·D. Drechsel·M. Gorchtein·A. Metz·M. Vanderhaeghen
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Abstract

A dispersion relation formalism for the virtual Compton scattering (VCS) reaction on the proton is presented, which for the first time allows a dispersive evaluation of 4 generalized polarizabilities at a four-momentum transfer $Q^2 \leq$ 0.5 GeV$^2$. The dispersive integrals are calculated using a state-of-the-art pion photo- and electroproduction analysis. The dispersion formalism provides a new tool to analyze VCS experiments above pion threshold, thus increasing the sensitivity to the generalized polarizabilities of the nucleon.

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B. Pasquini, D. Drechsel, M. Gorchtein, A. Metz, M. Vanderhaeghen. 2000-07-13. Dispersion relation formalism for virtual Compton scattering and the generalized polarizabilities of the nucleon. https://doi.org/10.1103/physrevc.62.052201

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