Dependence of the threshold of formation of an air breakdown plasma near copper mirrors on the absorption coefficient of their surface at the wavelength of 10.6 μ

An investigation was made of the influence of the absorption coefficient of copper mirrors on the threshold of formation of an air breakdown plasma formed by focusing CO₂ laser pulses on the surface of a mirror. An analysis was made of the various methods for cleaning the mirror surface. A single-valued dependence of the threshold energy density on the absorption coefficient of a mirror was obtained.