<title>HF chemical laser amplifier initiated by input pulse and not consuming external energy</title>

Abstract

An H₂ - F₂ amplifier initiated by radiation from a pulsed hydrogen fluoride laser is studied theoretically. Numerical calculations are made by taking into account the inhomogeneity of initial HF concentration appearing upon preparation of the laser mixture in experiments. The dependence of the specific laser output energy from a distance x from the radiation input to the amplifier medium for mixture H₂:F₂:O₂:He = 100:600:30:100 Torr is obtained. Change of initial pressure of HF molecules in the mixture on the distance x was described by the expression <i>p_o</i> + <i>C</i>sin(2&pi;x/<i>d</i>), where <i>P_o</i> = 0.1 - 0.5 Torr, <i>d</i> = 10 - 20 cm, <i>C</i> is the amplitude of deviation of HF pressure from its mean value. The theoretical specific output energy periodically depends on x according to the law of change of pressure HF. The energy gain (ratio of the energies of the output and initiating laser radiation) is equal to 5 for an amplification length 4 m at <i>p_o</i> = 0.1 Torr and <i>C</i>/<i>p_o</i> = 5%.