Electron beam dissociation of fluorine

Electron beams have been used previously to initiate hydrogen fluoride chemical laser action by dissociating fluorine containing compounds, and the results compared with flashlamp initiation. However, the comparison was qualitative in nature. In order to assess how useful electron beams are for initiating reactions by liberating fluorine atoms, it is necessary to know the yield of fluorine atoms per each ionizing collision of a primary electron. The object of the present investigation was to measure the yield for the case of 100 keV electrons injected into fluorine. The electron beam was a Simulation Physics Corporation machine producing a current density of 200 amp/cm², for a time of 300 nanosecs, at an energy of 100 keV. The electrons were injected into mixtures of fluorine, hydrogen, and helium and also mixtures of fluorine, hydrogen chloride, and helium at a total pressure of one atmosphere. The resulting fluorine atom concentration was monitored using two techniques: ultraviolet absorption by fluorine molecules for the mixture containing hydrogen and absorption of a probe HF laser for the mixture containing hydrogen chloride. The data will be presented.