Generation of quasimonochromatic transition radiation X-rays using a K-shell photoabsorption edge

We propose a simple method to produce quasimonochromatic X-rays by means of photoabsorption-edge transition radiation tuned by tilting a foil stack. We have calculated and measured energy spectra of transition radiation for two types of radiators. One is a titanium-foil stack, and the other is composed of a Kapton-foil stack and a titanium filter. For the first type, the spectra can be easily tuned by tilting the foil stack to the electron beam, and the energy width of X-rays is reduced to one-third of that for the normal incidence of electrons. The easy tunability and narrow width was also obtained for the second type. The two types of radiator show almost the same performance if an adequate condition is satisfied. However, the second type radiator is applicable in wider energy range of X-rays than the first type radiator. (C) 1999 Elsevier Science B.V. All rights reserved.