Traces on ion yields and electron spectra of Ar inner-shell hollow states with Free-Electron Lasers

TL;DR

This paper investigates how Free-Electron-Laser pulses create argon hollow states with inner-shell holes, analyzing ion yields and electron spectra to understand their formation and spectral signatures.

Contribution

It introduces a detailed analysis of argon hollow states with multiple inner-shell holes, including their formation dependence on pulse parameters and spectral signatures.

Findings

Even charged Ar ions can be more populated than odd ones.

Electron spectra reveal signatures of hollow states with two inner-shell holes.

Auger spectra can be extracted from two-electron coincidence measurements.

Abstract

We explore the formation by Free-Electron-Laser radiation of Ar hollow states with two or three inner-shell holes. We find that even charged Ar ion states can be more populated than odd charged Ar ion states. This depends on the pulse intensity and the number of energetically accessible inner- shell holes. Fully accounting for fine structure, we demonstrate that one electron spectra bare the imprints of Ar hollow states with two inner-shell holes. Moreover, we show how the Auger spectra of these hollow states can be extracted from two-electron coincidence spectra.