Dispersion representation of the D-term form factor in deeply virtual Compton scattering

Abstract

We review the dispersion relation formalism for the deeply virtual Compton scattering amplitudes, and derive a dispersive representation of the D-term form factor, using unsubtracted t-channel dispersion relations. Results for the D-term form factor as function of t as well as at t = 0 are shown in comparison with available model predictions and phenomenological parametrizations.