Extended use of the sealed HBr chemical laser by "Cl2activation"

A new passivation technique, which we call "Cl
2
activation," has been developed for the pulsed HBr chemical laser. Hundreds of HBr laser shots have been observed from the sealed H
2
+ Br
2
gas mixture as the result of the Cl
2
activation. Under normal conditions, HBr molecules accumulate in the reagent gas mixture after laser oscillation, and the accumulated HBr molecules hinder subsequent laser oscillations. In Cl
2
activation, Cl
2
molecules attach themselves to the stainless steel electrodes in the pin-rod TE-type laser tube. The attached Cl
2
molecules react with the HBr molecules which were produced by the laser reaction. As a result, HBr molecules do not accumulate in the gas mixture. The mixture returns to its original composition after each lasing. As a maximum, about 700 laser shots have been observed.