Characteristics of a pulsed chemical laser utilizing an H2–F2 mixture and initiated by radiation from an XeCl excimer laser

A study was made of the influence of the active mixture composition on the energy and temporal characteristics of an HF laser, for various diluents (He, Kr, Xe, N₂, SF₆). An efficiency of 1500%, measured relative to the ultraviolet initiation energy deposited in the mixture, was achieved utilizing an F₂ : O₂ : H₂ : SF₆ = 7.5 : 0.75 : 2.5 : 3.5 mixture at p = 110 Torr. The specific output energy increased in proportion both to the initiation energy (i.e., keeping the efficiency constant) and to the concentration of the fuel mixture (for a given initiation energy). An output energy of 38 J/liter was achieved for an F₂ : O₂ : H₂ : He = 25 : 2.5 : 2.5 : 20 (mixture (p = 0.5 atm) with a concentration of atoms created by the ultraviolet radiation of [F]₀~2×10¹⁶ cm^–3.