Mechanism of formation of the CN(B2Σ+) state from dissociative excitation reaction of BrCN with electron cyclotron resonance plasma of Ar

High-resolution emission spectra of the CN(B(2)Sigma(+)-X(2)Sigma(+)) transition and the resonance lines of Ar and Ar+ have been observed for the dissociative excitation reaction of BrCN with the electron cyclotron resonance (ECR) plasma of Ar. These spectra have been compared with those observed for the reaction with the microwave (MW) discharge flow of Ar. It is found that the energy transfer from the metastable state of Ar which proceeds predominantly in the MW discharge flow does not proceed in the ECR plasma. The electron density and temperature have been measured by an electrostatic-probe measurement. from which the kinetic analysis of formation of CN(B(2)Sigma(-)) has been conducted. The most dominant process of formation of the CN(B(2)Sigma(+)) state in the ECR plasma is considered to be the dissociative excitation of BrCN by the impact of high-energy free electrons, where the contribution of the recombination of BrCN+ with thermal free electrons cannot be excluded.