Excitation of low excited states of Ne I and He I by He+ + Ne collisions

Emission cross sections for the resonance lines of Ne I (744 and 736 \AA{}) and He I (584 \AA{}) have been investigated during collisions of ${\mathrm{He}}^{+}$ + Ne at energies from threshold to 9 keV. The threshold of excitation for the channel which dissociates into the upper state of the 736-\AA{} line is 21.7 \ifmmode\pm\else\textpm\fi{} 2.0 eV, and the large modulation depth in the total cross section shows this channel to be strongly coupled at an internuclear separation of 5.3 \AA{} to another excited channel which is presumed to be ${\mathrm{He}}^{*}(1s2s)+{\mathrm{Ne}}^{+}(2{p}^{5})$. The onset of excitation of the 744-\AA{} line occurs at 16.3 \ifmmode\pm\else\textpm\fi{} 0.5 eV, and the emission cross section exhibits oscillatory structure which is less pronounced than that of the 736-\AA{} line. Excitation of the 584-\AA{} line appears to occur through several channels.