Comparative study of the electron- and positron-atom bremsstrahlung

TL;DR

This paper presents a fully relativistic comparison of electron and positron bremsstrahlung in atoms, revealing how relativistic effects break the near symmetry observed in nonrelativistic regimes.

Contribution

It provides a detailed relativistic calculation of electron and positron bremsstrahlung, highlighting the differences caused by relativistic effects.

Findings

Relativistic effects significantly break electron-positron symmetry in bremsstrahlung spectra.

Comparison of single and double differential cross sections shows notable differences.

Stokes parameters of emitted photons vary distinctly between electrons and positrons.

Abstract

Fully relativistic treatment of the electron-atom and positron-atom bremsstrahlung is reported. The calculation is based on the partial-wave expansion of the Dirac scattering states in an external atomic field. A comparison of the electron and positron bremsstrahlung is presented for the single and double differential cross sections and the Stokes parameters of the emitted photon. It is demonstrated that the electron-positron symmetry of the bremsstrahlung spectra, which is nearly exact in the nonrelativistic regime, is to a large extent removed by the relativistic effects.