Ion and Electron Momentum Distributions from Single and Double Ionization of Helium Induced by Compton Scattering

TL;DR

This paper investigates the momentum distributions of helium ions and electrons resulting from double ionization caused by 40 keV photon Compton scattering, revealing close links to the nuclear and electron Compton profiles.

Contribution

It demonstrates that ion momentum distributions closely match the nuclear and electron Compton profiles, requiring highly correlated wavefunctions for accurate non-relativistic calculations.

Findings

Doubly charged ion momentum distribution aligns with the nuclear Compton profile.

Singly charged ion momentum distribution accurately reflects the electron Compton profile.

Highly correlated wavefunctions are essential for reproducing the observed distributions.

Abstract

We present the momentum distributions of the nucleus and of the electrons from double ionization of the helium atom by Compton scattering of photons with $h\nu=40$ keV. We find that the doubly charged ion momentum distribution is very close to the Compton profile of the nucleus in the ground state of the helium atom, and the momentum distribution of the singly charged ion to give a precise image of the electron Compton profile. To reproduce these results, non-relativistic calculations require the use of highly correlated initial- and final-state wavefunctions.