GAUGE DISCREPANCIES IN CALCULATIONS OF (GAMMA, 2E) ON HELIUM

We have studied the dependency and sensitivity of the triple different ial cross section (TDCS) for (gamma, 2e) on He with respect to the gau ge formulation that one employs to represent the TDCS. This analysis h as been performed using a variety of analytic initial-and final-state wavefunctions. It was found that the TDCS is very sensitive to the rep resentation of the final-state wavefunction in all geometries and all formulations of the TDCS. When the detected electrons are of unequal e nergy the TDCS is also sensitive to the initial-state wavefunction. Th e predictions using all combinations of initial-and final-channel wave functions are gauge dependent and vary enormously in absolute size.