Influence of two-photon processes on the x-ray emission spectrum of a laser plasma

It is shown that the Raman scattering of laser radiation and the stimulated two-photon emission may give rise to additional lines in the x-ray spectrum of a laser plasma. These lines are satellites of the forbidden transitions, which become comparable in intensity with the allowed lines at flux densities I₀ ~ 10¹⁴–10¹⁵ W/cm². Measurements of the ratios of the intensities of the laser satellites to the intensities of the allowed lines can be used to determine the intensity of the optical field and the density of electrons in a plasma.