Spectroscopic investigations of corona discharge in high pressure Helium at 300K

Gaseous Helium at 300K and pressure (0.1-3)MPa was excited using a corona discharge both for negative and positive high voltages. The light emitted from the ionization zone of the discharge was analyzed. The atomic lines observed was shifted and broadened due to interaction of radiators with surrounding atoms (the pressure broadening). Asymmetric shape of atomic line 706nm was recorded. Blue wing of the line is more intensive than its red wing. The reason of the phenomenon is the repulsive interaction between excited atoms with atoms in the ground state. The line shape is described as a convolution of Lorentz profile of the line center and a quasi-statistical profile of a blue wing of the line. Such analysis allows us to predict a weak heating of the gas in the ionization zone for positive corona and considerable heating for negative corona.