Gain distribution, population densities and rotational temperature for the (00°1)-(10°0) rotation-vibration transitions in a flowing CO<inf>2</inf>-N<inf>2</inf>-He laser

Small-signal gain coefficients in a flowing amplifying mixture of CO2-N2-He were measured on 46 individual rotation-vibration transitions in thePandRbranches of the(001)-(100)band in CO2. The resulting gain distribution as a function ofJwas in agreement with a Boltzmann distribution of population among the rotational levels of each vibrational state. The physical parameters characterizing the CO2laser levels were found to be{N₀₀₁}{N₁₀₀} = 2.27; {N₀₀₁}{Nₜₒₜₐₗ} ≥ 0.17;{N₁₀₀}{Nₜₒₜₐₗ} ≥ 0.08; T = 340 where Ntotalis the number of CO2molecules in the amplifying medium. The operating mixture was characterized by the following partial pressures and flow velocity: p(CO2) =0.65 torr; p(N2) =1.40 torr; p(He) =2.9 torr; v=192 cm/s.