The Rotational Temperature in High-Enthalpy Jets of Atmospheric- Pressure Nitrogen Plasma

Abstract

The paper deals with the spectroscopic determination of the temperature T v of population of low-lying vibrational levels of radiating electron terms of an N2 molecule and N 2 + molecular ion in different cross sections of a high-enthalpy jet of atmospheric-pressure nitrogen plasma. Use is made of the method of optimal fitting of the measured and simulated rovibronic spectra in some selected spectral range of the (0–1) and (1–2) bands of the first negative system of N 2 + ion and of the method of finding T v by the integral intensities of molecular bands (sequence Δv = −1 of the second positive system of N2). The obtained values of vibrational temperature are compared to the previously found values of rotational temperature T r and electron temperature T e . The pattern of variation of temperatures along the plasma jet in the zone of relaxation is discussed.