Investigation On The Diagnosis Of Plasma And Rovibrational Spectrum Of CO~+

The determination of plasma parameters is essential in the plasma physics.Among those all kinds of techniques,spectral diagnosis is an important and non-intrusive method to determine the parameters without any disturbance to the plasma.Some literatures have reported on the diagnosis of the temperature and electric field.This thesis focuses on the diagnosis of the ionization depth of glow discharge with different buffer gases employing optical heterodyne velocity modulation spectroscopy (OH-VMS).Additionally,this thesis reports the rotational study on the weak hot band (4,6) in the comet-tail system of CO⁺.And finally,a tentative spectral analysis on the neutral productions of the discharging of water buffered in rare gas is presented and future works are prospected.The thesis is arranged as flows,Chapter 1 gives a general introduction to this thesis.Chapter 2 introduces the theory and apparatuses of OH-VMS and OH-MR-VMS.Chapter 3 focuses on the diagnosis of the plasma.Taking N₂⁺ as the molecular probe,we investigate the ionization behaviors of nitrogen molecule buffered in different rare gas(alone and mixture) by OH-VMS.By studying the spectral intensity of an individual rovibronic line,the relative ionization depths are obtained.When assistant by the current determination,the absolute concentration of electron can also be determined.Chapter 4 gives a general introduction to the transition theory of ²âˆ-²âˆ‘⁺.Chapter 5 investigates the high resolution spectrum in the weak hot band(4,6) in the comet-tail system of CO⁺.The absorption spectrum is observed by OH-MR-VMS. 126 lines are assigned to the(4,6) band for the first time.Employing the effective Hamiltonians,the most accurate molecular constants of the levels involved are obtained by weighted nonlinear least-squares fitting combined with the 189 lines of(3, 6) band,and most of the constants are improved over twice.Finally,a tentative analysis on the concentration modulation spectrum of the discharging of water buffered in rare gas is presented in Chapter 6,and prospective investigation is suggested in Chapter 7 as well.