Spectroscopic investigation of corona discharges in liquid and high density gaseous nitrogen

This paper presents the results of a spectroscopic investigation of corona discharges in high pressure nitrogen gas (up to 10 MPa) and in liquid nitrogen. In gas, rotational temperatures T-r, and vibrational temperatures T-V of the excited state 2s(+)(C-3 Pi(u)) have been deduced from a comparison between computer generated synthetic spectra and experimental ones. In liquid phase, only the vibrational temperature could be measured. The ratio of (0-0) band intensity of 1s(-) transition on (2-5) band intensity of 2s(+) transition has been determined as a function of discharge current and density. From this ratio, the mean electron energy, <epsilon>, has been estimated.