Pavlov I. The nature of the fine structure of XeCl excimer lasing spectrum

The thesis concerns the nature of the fine structure in XeCl lasing. It is shown that the fine structure lines appear in the ranges of high density of rotational frequencies of various electron-vibrational transitions. The parameters of electric-discharge XeCl laser based on He:Xe:CF2Cl2 mixture were optimized. It is shown that the Freon-12 can be used as a possible halogen-carrier for an electro-discharged XeCl laser if requirements for the life time of the work mixture are not too strict. The influence of the resonator elements on the fine structure spectrum is studied. It is shown for the first time that in the case of resonator with highly reflective mirrors (~99%), the fine structure of a lasing spectrum depends on both the vibration-rotation spectrum of the molecule and the parameters of the discharge absorption lines. It is just the case when the fringed pattern in the lasing spectrum does not occur. The effect of isotopic composition of the working mixture on the fine structure spectrum is investigated for the first time. We have shown that more complete and, in some cases, more continuous infilling of the lasing spectrum of a XeCl laser could be achieved by changing the isotopic composition of the work mixture. The fine structure lines for molecular lasing spectra of 124Xe35Cl, 129Xe35Cl, 136Xe35Cl and XeCl (in the natural isotopic state) are described. The fundamental vibrational constants for XeCl molecule are computed using the least-squares fitting of the experimental spectral data for individual types of isotope molecules.