Radiative-emission analysis in charge-exchange collisions of O6+ with argon, water, and methane

Abstract

Processes of electron capture followed by Auger and radiative decay were investigated in slow ion-atom and -molecule collisions. A quantum-mechanical analysis which utilizes the basis generator method within an independent electron model was carried out for collisions of $\mathrm{O}{}^{6+}$ with Ar, ${\mathrm{H}}_{2}\mathrm{O}$, and ${\mathrm{CH}}_{4}$ at impact energies of 1.17 and 2.33 keV/amu. At these impact energies, a closure approximation in the spectral representation of the Hamiltonian for molecules was found to be necessary to yield reliable results. Total single-, double-, and triple-electron-capture cross sections obtained show good agreement with previous measurements and calculations using the classical trajectory Monte Carlo method. The corresponding emission spectra from single capture for each collision system are in satisfactory agreement with previous calculations.