Emission spectra of argon and nitrogen plasmas realized in a high current (I ≤ 500A) plasmatron with a divergent stabilizing channel have been taken in the range 220−860nm by the use of two automated systems for multichannel analysis. The spectra of highly ionized argon and nitrogen plasmas at atmospheric pressure thus obtained have been extensively investigated in the vicinity of the cathode where the specific energy released is about 50
kW/cm3 as well as in the plasma relaxation zone at different distances downstream from the
energy input region. For all the domains mentioned the electron component parameters concentration
ne and temperature Te have been determined.