Chemical kinetics and gasdynamics of a Q-switched iodine laser with an optically thick active medium

A calculation technique is proposed and numerical calculations are made of the spatial distributions of the energy stored in an iodine laser with an optically thick active medium pumped by a planar blackbody radiation source in the 180—700 nm spectral range. In describing the evolution of the laser active medium, simultaneous allowance is made for: relaxation and chemical processes (using recent data on their rate constants), heat liberation and its influence on the rates of elementary processes, absorption band profiles, and motion of the gas, which is mainly caused by nonuniform heating of the medium. Calculations are made of the laser output energy as a function of the degree of dilution with the buffer gas and the single-pulse switching time, and of the efficiency. The spatial distributions of the population inversion, gas temperature, density, velocity and pressure, pumping rate, and microparticle concentration are determined for different times.