Generating collimated intense monochromatic beams of soft x radiation from an X-pinch in the wavelength region 0.4–1.0 nm by means of spherical crystal mirrors

The generation of collimated intense monochromatic beams of soft x radiation in the wavelength interval 0.4–1.0 nm from an X-pinch is reported. This is the first such report. High-quality mica crystals with dimensions of 10 × (30–35) mm were used to form beams with an energy of 2–3.2 μJ, a wavelength spread Δλ/λ=4 · 10^–3, and a divergence of 5 · 10^–4 rad. The mica crystals were bent into spherical surfaces with a radius of curvature of 10 or 25 cm. The characteristics of the resulting beams are compared with those of the beams from Ta lasers, with a wavelength ~4.5 nm, which are the shortest-wavelength x-ray lasers which have been reported to date. This comparison shows that the beams obtained in the present study are better than those from the Ta laser in terms of several characteristics (divergence, wavelength, and efficiency), while they are worse (but not greatly so) in terms of certain other characteristics (wavelength spread and energy in the pulse. It is thus possible today to solve many practical problems involving the use of collimated intense monochromatic beams of soft x radiation in the wavelength interval 0.25–2.0 nm. These problems can be solved with the help of the x radiation from an X-pinch or from plasmas produced by picosecond or femtosecond table-top lasers and short-focal-length, large-aperture crystal mirrors.