Production of positronium chloride: A study of the charge exchange reaction between Ps and Cl$^{-}$

TL;DR

This paper investigates the formation of positronium chloride through charge exchange reactions with chloride ions, using advanced theoretical models to calculate cross sections across a range of energies, highlighting the importance of electronic correlation effects.

Contribution

It provides detailed cross section calculations for PsCl formation using ab-initio methods and emphasizes the impact of electronic correlation on the results.

Findings

Ps(${n=2}$) channel is particularly effective for PsCl production.

Electronic correlation significantly alters the shape of the cross section.

Accurate modeling requires beyond mean-field approaches.

Abstract

We present cross sections for the formation of positronium chloride (PsCl) in its ground state from the charge exchange between positronium (Ps) and chloride (Cl$^-$) in the range of 10 meV - 100 eV Ps energy. We have used theoretical models based on the first Born approximation in its three-body formulation. We simulated the collisions between Ps and Cl$^-$ using ab-initio methods at both mean-field and correlated levels extrapolated to the complete basis set limit. We have investigated Ps excited states up to ${n=4}$. The results suggest that the channel Ps(${n=2}$) is of particular interest for the production of PsCl in the ground state, and shows that an accurate treatment of the electronic correlation leads to a significant change in the global shape of the PsCl production cross section with respect to the mean-field level.