The Off-forward Quark-Quark Correlation Function
  The properties of the non-forward quark-quark correlation function are examined. We derive constraints on the correlation function from the transformation properties of the fundamental fields of QCD occurring in its definition. We further develop a method to construct an ansatz for this correlator. We present the complete leading order set of generalized parton distributions in terms of the amplitudes of the ansatz. Finally we conclude that the number of independent generalized parton helicity changing distributions is four. 
Sabrina Casanova