It is shown that a solution to the difficulty encountered in reproducing simultaneously the experimental longitudinal and transverse response functions deduced from deep inelastic electron scattering may be found in a consistent treatment of the electromagnetic interaction in a Dirac equation in which Lorentz scalar and vector potentials are explicitly introduced. Results for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ are given and compared with experiments.

• Received 6 December 1983

DOI:https://doi.org/10.1103/PhysRevC.30.731