Radiative characteristics and electronic transport coefficients plasma-based water vapor

Abstract

The results of studies of the positive column plasma radiation of a longitudinal glow discharge in water vapor and mixtures He- H 2 O with partial pressures p (H 2 O) = 50-200 Pa; 2.0-2.5 kPa and p (He) = 0,1-1,5 kPa are presented. Analysis of radiation in the spectral range 130-350 nm showed that at low water vapor pressure the main in the emission plasma spectra were bands of hydroxyl OH (X-A) (Δλ = 280-320 nm) and OH (A-C) (Δλ = 140 -200 nm). The optimization of the hydroxyl emission bands OH intensity, depending on the water vapor pressure and partial composition of the He - H 2 O mixture, as well as the discharge current is conducted. Optimum conditions of the radiator at the bands OH (X-A) and OH (A-C) are identified. Based on the effective interaction cross sections database of low energy electrons with water molecules, for a discharge in water vapor and mixtures of p (Re) - p (H2O) = 9.1 compiled by us the electron energy distribution functions and electron kinetic coefficients in the range of the parameter E/N = 1 - 300 Tg are calculated. Analysis of helium influence on the positive column plasma parameters in a strong dilution of water vapor with helium is conducted. The results are of interest for the optimization and modeling of spontaneous UV-VUV radiation gas-discharge sources on the basis of the decay products of water molecules in the low density plasma.