On Anisotropy and Spatial Dependence of Doppler-Induced Broadening Due to Heavy-Particle Excitation

We study the anisotropy of anomalously broadened
$\hbox{H}\alpha$
lines in a low-current Townsend discharge in hydrogen. Monte Carlo simulation based on the best available data was used to predict angular distributions of heavy particles and spatial dependence of line profiles due to heavy-particle excitation at 10 kTd.