Study of the dynamics of spatial – energy and spectral characteristics of a cw chemical HF laser with a three-jet nozzle array

The development of spatial – energy and spectral characteristics of a cw chemical HF laser with a three-jet nozzle array that was built using the nozzle – nozzle – nozzle mixing scheme is experimentally studied as a function of the degree of secondary dilution of the active medium with helium. The energy and spectral characteristics of laser emission were found to be unstable in time and dependent on the cavity configuration. The length of the lasing region upon the secondary dilution reached 10 – 12 cm, whereas the spacing between the onset. of this region and the edge of the nozzle array was independent of the degree of dilution. The possibility of selecting spectral lines by varying the position of the optical cavity axis and the degree of secondary dilution was demonstrated.