Role of final state interactions in quasielastic 56Fe(e,e') reactions at large ||q-->||

A relativistic finite nucleus calculation using a Dirac optical potential is used to investigate the importance of final state interactions (FSI) at large momentum transfers in inclusive quasielastic electronuclear reactions. The optical potential is derived from first-order multiple scattering theory and then is used to calculate the FSI in a nonspectral Green's function doorway approach. At intermediate momentum transfers excellent predictions of the quasielastic ⁵⁶Fe(e,e') experimental data for the longitudinal response function are obtained. In comparisons with recent measurements at ||q-->||=1.14 GeV/c the theoretical calculations of R_L give good agreement for the quasielastic peak shape and amplitude, but place the position of the peak at an energy transfer of about 40 MeV higher than the data.