Coulomb distortion effects in quasi-elastic (e,e') scattering on heavy nuclei

TL;DR

This paper investigates Coulomb distortion effects in quasi-elastic electron scattering on heavy nuclei, demonstrating that at high energies, the effective momentum approximation reliably accounts for these distortions regardless of nuclear current models.

Contribution

It provides a numerical solution to the Dirac equation for electrons in nuclear Coulomb fields and compares approximate models to show the effectiveness of the effective momentum approximation.

Findings

Coulomb distortions can be accurately modeled by the effective momentum approximation at high energies.

Exact electron states are obtained by solving the Dirac equation numerically.

The approximation is robust across different nuclear current descriptions.

Abstract

The influence of the Coulomb distortion for quasi-elastic (e,e') scattering on highly charged nuclei is investigated in distorted wave Born approximation for electrons. The Dirac equation is solved numerically in order to obtain exact electron continuum states in the electrostatic field generated by the charge distribution of an atomic nucleus. Different approximate models are used to describe the nucleon current in order to show that, at high electron energies and energy-momentum transfer, the influence of Coulomb distortions on (e,e') cross sections can be reliably described by the effective momentum approximation, irrespective of details concerning the description of the nuclear current.