Light-Cone Wavefunction Representation of Deeply Virtual Compton Scattering

Abstract

We give a complete representation of virtual Compton scattering ${\gamma }^{\ast }p\to \gamma p$ at large initial photon virtuality $Q^2$ and small momentum transfer squared $t$ in terms of the light-cone wavefunctions of the target proton. We verify the identities between the skewed parton distributions $H(x,\zeta ,t)$ and $E(x,\zeta ,t)$ which appear in deeply virtual Compton scattering and the corresponding integrands of the Dirac and Pauli form factors $F_1(t)$ and $F_2(t)$ and the gravitational form factors $A_q(t)$ and $B_q(t)$ for each quark and anti-quark constituent. We illustrate the general formalism for the case of deeply virtual Compton scattering on the quantum fluctuations of a fermion in quantum electrodynamics at one loop.

Comments: References added and minor revisions made in text. Version to appear in Nucl. Phys. B