Gasdynamically Cooled CO-Laser with RF-Excitation: Design and Performance.

A gasdynamically cooled CO-laser with a dielectrically stabilized RF-discharge in the subsonic region is described and experimental results are presented. The gas is excited at pressures of about 500 mbar in a discharge tube with a rectangular cross-section. The laser gas is cooled to a temperature of approximately 90 K by an adiabatic expansion in a two-dimensional supersonic nozzle. After extraction of laser energy in a triple pass resonator the gas is recompressed in a supersonic diffuser and by a Roots pump system