A perturbative treatment of double gluon exchange in γ∗-proton DIS

A new model for the exchange of two gluons between the virtual photon and the proton, in non-diffractive deeply inelastic electron–proton scattering, is developed and studied. This model relies on a perturbative calculation previously applied to diffraction, and a general result from Regge theory. As a first application of the model, we study corrections to the momentum transfer to the quark–anti-quark pair at the photon-vertex. We find a significant enhancement of the cross-section at ∼Q2 momentum transfers, and large negative corrections for small momentum transfers. The implication of this result for jet-distributions measured at HERA is discussed.