Reggeometry of Deeply Virtual Compton Scattering and Exclusive Vector Meson Production at HERA

A Reggeometric (Regge+Geometry) model, based on the observed proportionality between the forward slope of the differential cross section and the interaction radius, the latter depending on virtuality Q2 of the incoming virtual photon and on the mass M 2 of the produced particle, is constructed. The objective of this study is the dependence of the Regge-pole amplitude on the virtuality Q2 and masses of the external particles, which remains an open problem for the theory. The present analysis is based on the HERA data on Deeply Virtual Compton Scattering (DVCS) and exclusive diffractive Vector Meson Production (VMP). We treat each class of reactions separately, anticipating a further study that will include both a soft and a hard component of the unique pomeron.