N(2D) and N(2P) metastable production by electron collisions in a D.C. glow discharge

2014 The atomic nitrogen metastable densities of N(2D) and N(2P) have been measured by optical absorption in a continuous glow dis harge. Electronic densities have been measured with a microwave resonant cavity. The evolution of N(2D) and N(2P) densities as a function of electronic density allows the estimation of the overall creation coefficient by electronic collisions CeM : e + N2 $$ e + N(2D, 2P) + N. This coefficient is of the same order of magnitude for N(2D) and N(2P) and lies between 1.5 x 10-10 and 4 x 10-11 cm3 s-1 for a pressure range between 0.5 and 1.5 torr (tube radius R = 1 cm). For currents higher than 20 mA the density of N(2P) is larger than the N(2D) density (approximately a factor of two at 50 mA). J. Physique 41 (1980) 243-250 ’ MARS 1980,