DOUBLE-CRYSTAL HIGH-RESOLUTION X-RAY SPECTROSCOPY OF LASER-PRODUCED PLASMAS

A double-crystal x-ray spectrometer (DCS) has been used to obtain high-resolution x-ray spectra of laser-produced plasmas. The DCS has a high dispersion, and thus can obtain highly resolved spectra in circumstances where the resolution of a conventional single-crystal. Bragg spectrometer at comparable source-to-detector distances would be limited by the source size. In addition the DCS also yields unit-magnification one-dimensional spatial resolution in the direction perpendicular to the spectral direction. The instrument produces two spectra symmetrically disposed about a central wavelength, which makes it especially useful for measuring spectral line shifts. Analysis of the spectra from hydrogenic aluminium an helium-like chlorine indicates a resolving power (lambda/DELTAlambda) greater than 2500 and a spatial resolution better than 30 mum.