Excitation of H Atoms to the n=3 States by the Impact of 10 - to 35-keV Ground-State H Atoms on He, Ne, Ar, H2, O2, and N2

Abstract

Absolute cross sections have been measured for the excitation of hydrogen atoms to the $3s$, $3p$, and $3d$ states by the impact of ground-state hydrogen atoms on He, Ne, Ar, ${\mathrm{H}}_2$, ${\mathrm{O}}_2$, and ${\mathrm{N}}_2$ in the energy range from 10 to 35 keV. In this energy range the cross sections for the different angular momentum states are generally the same order of magnitude (${10}^{-18\mathrm{}}$ ${\mathrm{cm}}^2$). Excitation to the $s$ state is more competitive with the $p$-state excitation at the $n=3\mathrm{}$ level than at the $n=2\mathrm{}$ level. Excitation to the $3d$ state is not as likely as excitation to the $3s$ or $3p$ states. Cross sections for the production of Balmer $\alpha$ radiation have been computed. Polarization fractions for the $3d\to 2p$ radiation have also been measured.