Improved effective momentum approximation for quasielastic (e,e') scattering off highly charged nuclei

We address the problem of including Coulomb distortion effects in inclusive quasielastic (e,e') reactions using an improved version of the effective momentum approximation. Arguments are given that a simple modification of the effective momentum approximation, which is no longer applicable in its original form in the case of highly charged nuclei, leads to very good results. A comparison of the improved effective momentum method with exact calculations is given. A critical remark concerns recent experiments with inclusive quasielastic positron scattering.