CARS spectroscopy of radio-frequency discharge plasma in hydrogen

The population of the vibrational and rotational levels of hydrogen is studied by the narrow-and broadband CARS spectroscopy in capacitive and inductive-capacitive radio-frequency discharge plasmas. Computational codes are developed to analyze and process CARS spectra of hydrogen obtained under conditions of disturbance of thermodynamic equilibrium over internal degrees of freedom of molecules. To interpret the measurement results, a model is developed, which makes it possible to calculate the vibrational temperature in radio-frequency discharge plasmas. It is shown that the broadband CARS spectrometer in combination with the software package developed appreciably reduces the time necessary to determine the vibrational and rotational temperatures.