Vibrational and rotational–translational temperatures in N_2 by interferometric measurement of the pure rotational Raman effect

Vibrational and rotational–translational temperatures in electrical discharges in nitrogen gas were independently measured by the Fabry–Perot interferometric observation of the rotational Raman effect. For two different experimental arrangements of the discharge geometry in the gas cell, vibrational temperatures of 2356 and 1930 K were measured. Less-accurate determinations of the rotational–translational temperature indicate a much-lower temperature of 400 ± 10 K with the electrical discharge on. These temperatures are in good agreement with previous Raman spectroscopic observations on electrical discharges in nitrogen. In addition, the vibration-rotation interaction constant, αe, has been determined to be 0.01751 ± 0.00022 cm−1.