Size effect on polarization bremsstrahlung emission from xenon clusters

TL;DR

This study investigates how the size of xenon clusters influences polarization bremsstrahlung emission when 0.7 keV electrons scatter off them, revealing a significant size-dependent effect.

Contribution

It introduces a novel measurement method for absolute differential cross sections and demonstrates the first observed size effect on polarization bremsstrahlung in xenon clusters.

Findings

Polarization bremsstrahlung dominates the differential cross section.

Cluster size significantly affects the polarization bremsstrahlung formation.

A new method for absolute intensity measurement was developed.

Abstract

We measured the spectral distribution of the absolute differential cross section of both ordinary and polarization ultra-soft X-ray bremsstrahlung for 0.7 keV electrons scattered on substrate-free nanoclusters of xenon. Clusters were produced in a supersonic gas jet expanding adiabatically into a vacuum. An original method based on absolute measurements of the intensity of the atom and cluster emission in the vacuum ultraviolet and ultra-soft X-ray spectral regions was used to determine the cluster density in the scattering area. The bremsstrahlung arising from scattering of electrons on clusters had a polarization component which dominated the differential cross section. For the first time, cluster size effect on the formation of the polarization bremsstrahlung was found for xenon.