X-ray spectrum determination from the angular dispersion of radiation in adiamond prism

The X-ray spectrum of hard polychromatic radiation with energies of up to 4 0 keV was obtained from the angular dispersion of the radiation beam in a d iamond prism. In contrast to the classical optical scheme, the beam to be a nalyzed is passed through the entrance face of the prism without refraction and is directed onto the exit face at a glancing angle similar to (2 delta )(1/2), where delta is the real part of the decrement of the refractive ind ex for the short-wavelength edge of the spectrum. The spectrum distortions caused by the intersection of the reciprocal lattice points by the Ewald sp here at a fixed number of wavelengths lambda are minimized by the use of th e angular divergence of the beam of similar to 10' in the plane perpendicul ar to the refraction plane. In the energy range of 8-9 keV, an energy resol ution of less than 100 eV was obtained, which exceeds the corresponding par ameter for cooled semiconductor detectors. The measuring scheme suggested m akes it possible to solve the problem of the analysis of spectra of directi onal X-ray beams when studying fast nonstationary generation processes. (C) 2001 MAIK "Nauka/Interperiodica".