would be expected from a typical tube type laser which did not contain the fin ring segments the theory behind this improvement in output power is based on the fact that carbon dioxide lasers are limited by the ability of extracting heat from the laser gas in a normal tube type laser this heat extraction is limited by the thermal conductivity of the laser gas mixture since the laser gas is at a low pressure and also has a low average atomic weight it is not practical with acceptable pressure drops to reach a condition where turbulent flow can take place turbulent flow is the condition where random eddies cause rapid mixing of the gas and thereby increase the heat transfer rate over what would normally be expected for laminar flow the fin rings 20 are oriented so that gas flowing through the laser tube is redirected by the fin groups and broken up into four stable counterrotating vortices as shown in fig2 these vortices are stable unlike turbulent flow and they are optimized for transferring gas from the center of the tube where it is heated to the walls of tube where it can be cooled also the four vortex condition shown in fig2 is the optimum condition for stabilizing the electrical discharge that is normally the electrical discharge is deflected by any transverse gas flow while the four vortex flow shown in fig2 also slightly deflects the gas discharge it does not cause it to become unstable or to move away from the center of the tube it is also to be expected that further increases in the output power per unit length are possible by optimizing the fin size.