Microwave conductivity of a plume formed by laser evaporation of materials

An experimental investigation was made of the microwave absorption by a dense vapour in a laser plume formed at the surfaces of targets made of different materials. The plume was located at antinodes of an electric or a magnetic field in a standing wave. Measurements were made of the conductivity of the plume and of the brightness temperature of its radiation. The results were interpreted on the basis of a microscopic percolation model.