ELECTRON-DIFFUSION IN THE FAST-AXIAL-FLOW CO2-LASER

It is pointed out that the electron diffusion driven by collisions bet ween electrons and neutral molecules cannot explain the radial profile s of electron concentrations observed in the fast-axial-flow continuou s wave industrial CO2 laser plasma. Based on the approximations of the k-epsilon turbulence model, a simplified model of the turbulent elect ron diffusion is developed. Predicted radial profiles of electron conc entration in the laser cavity and experimentally observed profiles are shown to be in reasonable agreement ff we assume that the electron de nsity at the boundary is equal to about 0.6 of the maximum electron de nsity.