Electronic processes in collisions between nitrogen ions and hydrogen atoms

TL;DR

This study calculates cross sections for electronic processes in N^{4+} and hydrogen collisions across a wide energy range, providing data crucial for understanding fusion plasma behavior.

Contribution

It introduces a comprehensive semiclassical approach to compute cross sections for multiple electronic processes in N^{4+}-H collisions, including new data for excitation and ionization.

Findings

Electron capture cross sections agree well with experimental data.

New data provided for target excitation and ionization processes.

Discrepancies in previous data are analyzed and discussed.

Abstract

In order to interpret and predict the behavior and properties of fusion plasma, accurate cross sections for electronic processes in collisions between plasma impurities and atomic hydrogen are required. In this work, we investigate the electron capture (or charge exchange), target excitation, and ionization processes occurring in collision of ${\rm N}^{4+}$ with atomic hydrogen in a broad energy domain ranging from 0.06 to 225 keV/u. We consider ${\rm N}^{4+}$ ground state ${\rm N}^{4+} (2s)$ and also ${\rm N}^{4+} (2p)$ since the impurities in the edge plasma environment may be excited due to collisions with electrons and ions/atoms. Total and partial cross sections in both spin-averaged and spin-resolved cases are calculated using a two-active-electron semiclassical asymptotic-state close-coupling approach. For electron capture cross sections the present results show the best overall agreement with available experimental data for both total and partial cross sections, and the origins of observed discrepancies are discussed. Furthermore, we provide new data for target excitation and ionization processes, which are essential to improve our understanding of this relevant collision system.