Etat Stationnaire dans des Plasmas CO2–N2, CO2-He et CO2–N2–He Produits par Décharge Electrique

Abstract

Small signal gain coefficients in a flowing amplifying mixture of CO2–N2, CO2–He, CO2–N2–He at different partial pressures have been measured for several individual rotation–vibration transitions in the P and R branches of the 00°1–10°0 band of CO2. These gain measurements have been done using a single line, single mode laser; the power stability of this laser is better than 1.5 × 10−2 during 1 h. If we assume a Boltzmann distribution of population among the rotational levels characterized by a temperature TR not in equilibrium with the translational motion of the gas, we can calculate the populations of the lower and upper laser levels and the rotational temperature for several CO2–N2, CO2–He, CO2–N2–He mixtures. The calculations show that N2 and He have a very different action on the populations and on the rotational and translational temperatures.The vibrational temperatures for the mixtures have been calculated using a model proposed by Moore et al.