Non-ionizing cross section of electron scattering on atoms in matter accounting for dynamical screening effect

TL;DR

This paper introduces a comprehensive model for non-ionizing electron scattering in matter that accounts for dynamical screening effects, applicable across a wide energy range, and validated through simulation of ion track formation.

Contribution

The paper presents a novel formalism based on the dynamic-structure factor to unify electron scattering descriptions from low to relativistic energies, incorporating dynamical screening effects.

Findings

Model accurately describes electron scattering across energy ranges.

Simulation of ion tracks in quartz agrees with experimental data.

Formalism reduces to phonon scattering at low energies.

Abstract

We present a model of non-ionizing scattering of electrons on atomic ensemble in matter, applicable in a wide electron energy range from ~eV up to relativistic ones. The approach based on the dynamic-structure factor formalism considers collective response of the atomic and electronic systems of a target. It accounts for dynamical screening of atomic nuclei in matter by valence (collective) and core-shell electrons during the scattering events, dependent on the incident electron velocity. The proposed formalism for the cross section enables us to describe in a unified manner the electron scattering on the ensemble of isolated atomic nuclei at high incident electron energies, reducing to the scattering on phonons with decrease of the energy. Our model can be used, e.g., in transport Monte Carlo codes to describe the energy exchange between excited electrons and atomic ensemble in matter. An example of swift heavy ion track formation in quartz simulated with the proposed cross section shows a reasonable agreement with the experiment validating the model.