Spectroscopic determination of vibrational and rotational temperatures of NO molecules in N2-O2 mixture microwave discharge

By using an optical emission spectroscopic measurement method, the vibrational and rotational temperatures of nitrogen mbnoxide molecules are obtained for N-2-O-2 mixture microwave discharge plasma. We experimentally observed the gamma-band (195-340 nm) spectrum of nitrogen monoxide. We also developed a method of theoretical calculation for its vibrational and rotational spectrum, with which we can fit the experimental results theoretically, so that the vibrational and rotational temperatures can be determined. Some experiments are carried out to examine relaxation process of excited states of the N-2-O-2 gas mixture plasma together with its N-2 ratio dependence. We discussed the dominant molecular processes and excitation kinetics for the formation of NO A(2)Sigma(+) state under different discharge conditions, particularly on the N-2-O-2 mixture ratio. (C) 2015 The Japan Society of Applied Physics