Investigating the suppressions for the longitudinal structure function in high energy quasielastic scattering from Fe-56

Abstract

We investigate the cross sections for inclusive (e, e') reaction from Fe-56 in quasielastic region at large electron energies (2-4GeV) and large three momentum transfer (0.5-1.5 GeV/c). We use a relativistic mean-field single particle model for the bound and continuum nucleon wave functions based on the (sigma - omega) model and we include the effects of electron Coulomb distortion in the calculation. The results are compared to high energy data from SLAC and more recent data from Jefferson Laboratory, particularly for the kinematics where the quasielastic process is expected to dominate the cross section with the energy transfer less than 500 to 600 MeV. The effects of the predicted weakening of the strong scalar and vector potentials of the (sigma - omega) model at high energy are discussed. Possible evidence for "longitudinal suppression" or modifications of nucleon form factors in the medium is considered, but neither is necessary to explain the quasielastic data for four momentum transfers less than 1 (GeV/C)(2).