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arXiv · hep-ph/0102335

Dispersion relation formalism for virtual Compton scattering off the proton

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

We present in detail a dispersion relation formalism for virtual Compton scattering (VCS) off the proton from threshold into the $Δ(1232)$-resonance region. Such a formalism can be used as a tool to extract the generalized polarizabilities of the proton from both unpolarized and polarized VCS observables over a larger energy range. We present calculations for existing and forthcoming VCS experiments and demonstrate that the VCS observables in the energy region between pion production threshold and the $Δ(1232)$-resonance show an enhanced sensitivity to the generalized polarizabilities.

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B. Pasquini, M. Gorchtein, D. Drechsel, A. Metz, M. Vanderhaeghen. 2001-02-27. Dispersion relation formalism for virtual Compton scattering off the proton. https://doi.org/10.1007/s100500170084

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