Dissociative recombination of the CH$^+$ molecular ion at low energy

TL;DR

This study investigates the dissociative recombination of CH$^+$ ions at low energy using multichannel quantum defect theory, considering multiple electronic states, and achieves results consistent with experimental storage ring data.

Contribution

It introduces an improved model that fully accounts for ionization channels and accurately evaluates the reaction matrix, enhancing previous theoretical approaches.

Findings

Results agree with storage ring measurements

Complete ionization channels are crucial for accurate modeling

Multiple electronic states influence recombination dynamics

Abstract

The reactive collisions of the CH$^+$ molecular ion with electrons is studied in the framework of the multichannel quantum defect theory, taking into account the contribution of the core-excited Rydberg states. In addition to the $X^1\Sigma^+$ ground state of the ion, we also consider the contribution to the dynamics of the $a^3\Pi$ and $A^1\Pi$ excited states of CH$^+$. Our results - in the case of the dissociative recombination in good agreement with the storage ring measurements - rely on decisive improvements - complete account of the ionisation channels and accurate evaluation of the reaction matrix - of a previously used model.