Long-wave X-ray radiation mirrors

Problems of obtaining mirrors for long-wave length (200-20 Å) X-radiation are discussed. Results of the investigation of roentgenooptical characteristics of multilayer periodical C-Re, C-W and C-Ta structures with periods 60–80 Å have been analyzed. The layer thickness of the heavy elements varied from 3 to 25 Å. The following characteristics have been recorded in the wavelength range λ = 50–80 Å; reflection coefficient up to 20%, resolution λ/Δλ = 7–14, width of the angular dependence R(θ)Δθ ≈ 2°. The number of effectively reflecting pairs of layers, N_max = 17, has been determined from the position of secondary diffraction maxima.