Vol. 19, issue 02-03, article # 1

Abstract:

Using a self-consistent mathematical model of a He-Sr⁺ recombination laser developed, we have investigated evolution of the radial distribution of plasma parameters and lasing characteristics in a pulse-periodic regime of the laser operation. The calculations performed show a good agreement with the experimental data. We have also studied, by means of mathematical modeling, the phenomena of contraction and decontraction. It is established that contraction of the pulse-periodic discharge in the pure helium is caused by thermal plasma inhomogeneity formed by a series of pulses. It is shown that self-decontraction of the gas-discharge, when metal atoms are introduced into the pure inert gas, is caused, in the first place, by the low ionization potentials of the strontium atoms. This leads to almost complete double ionization of the strontium atoms practically over the entire cross section of the discharge tube. At the same time, spatial stabilization of the helium ionization process also occurs. As a result, flattening of the radial profile of the electron concentration occurs as the strontium atom concentration increases.