Radiative stabilization following double-electron capture in slowNe10++Hecollisions

Abstract

Individual contributions to radiative stabilization in ${\mathrm{Ne}}^{10+}+\mathrm{He}$ collisions were studied at projectile energies from 1 to 150 keV. In these collisions doubly excited states ${3lnl}^{\ensuremath{'}}$ and ${4lnl}^{\ensuremath{'}} (n>~4)$ can be produced by uncorrelated two-electron transitions or by dielectronic processes caused by the electron-electron interaction. Compared to our previous study of stabilization, we extended the projectile-energy range down to 1 keV and the present analysis is based entirely on experimental data. Radiative stabilization was evaluated by combining our recent results for Auger decay cross sections with available radiative and nonradiative branching ratios. The total amount of radiative stabilization was found to be nearly constant $(\ensuremath{\approx}0.35)$ within the studied energy range. However, the individual contributions to stabilization were found to change significantly. At 1 keV the major contribution to stabilization is shown to be due to the decay of the nonequivalent electron configurations ${3lnl}^{\ensuremath{'}} (n>~6)$ produced during the collision by the dielectronic process of autoexcitation.