Abstract: A recirculating gas laser includes a gas-containing closed chamber having optically aligned mirrors adjacent the ends with a closed loop gas recirculation path, means for moving the gas around that path, and means for producing an electrical discharge in the gas, generally transversely of the optical axis. A heat exchanger for cooling the gas is interposed in the gas flow path, and means for supporting the mirrors extend longitudinally of the chamber and are positioned within the gas flow path to receive the cooled gases thereagainst, this support means being mounted to the chamber by other means which isolate the support from expansion and contraction of the chamber.

Abstract: Apparatus is described for producing an electric glow discharge in gas flowing along a channel with the discharge extending in a direction generally transverse to the flow, such apparatus including a first electrode disclosed adjacent a first wall of the flow channel and a generally planar second electrode disposed adjacent a second wall of the flow channel opposed to the first wall, the second electrode being formed of a material having a resistivity in the range of 10.sup.2 to 10.sup.6 ohm-centimeters. Means for electrically energizing the first and second electrodes to establish the glow discharge are also provided.