Semirelativistic $1s-2s$ excitation of atomic hydrogen by electron impact

TL;DR

This paper presents a semirelativistic theoretical analysis of electron-induced excitation of hydrogen's 1s to 2s transition, examining relativistic, spin, and dynamic effects across different regimes.

Contribution

It introduces a semirelativistic model using Dirac spinors and Darwin wave functions for the first Born approximation in hydrogen excitation studies.

Findings

Relativistic and spin effects are significant in the relativistic regime.

The study details the dynamic behavior of differential cross sections across regimes.

Nonrelativistic and moderate relativistic regimes are thoroughly analyzed.

Abstract

In the framework of the first Born approximation, we present a semirelativistic theoretical study of the inelastic excitation ($1s_{1/2}\longrightarrow 2s_{1/2}$) of hydrogen atom by electronic impact. The incident and scattered electrons are described by a free Dirac spinor and the hydrogen atom target is described by the Darwin wave function. Relativistic and spin effects are examined in the relativistic regime. A detailed study has been devoted to the nonrelativistic regime as well as the moderate relativistic regime. Some aspects of this dependence as well as the dynamic behavior of the DCS in the relativistic regime have been addressed.