Electron-ion bremsstrahlung of a non-equilibrium plasma

Abstract

Electron-ion bremsstrahlung in a weakly ionized uniform non-stationary plasma (in the absence of external fields) is investigated. The momentum transfer frequencyν ₁ is assumed to be velocity independent (H₂ and He plasmas). The respective Fokker-Planck equation is applied for two initial electron distributions: maxwellian with the temperatureT ₀, and delta distribution (C δ(ν−ν ₀)). The results are expressed analytically. In the case of initial delta distribution a different behaviour of intensity is found forq (ratio of final and initial temperatures) more or less than 3/2. From the calculations one may deduce that fors=(2mν₁ t/M)≳5 the difference between equilibrium and non-equilibrium intensities becomes insignificant.