Resonant Diffusive Radiation in Random Multilayered Systems
  We have theoretically shown that the yield of diffuse radiation generated by relativistic electrons passing random multilayered systems can be increased when a resonant condition is met. Resonant condition can be satisfied for the wavelength region representing visible light as well as soft X-rays. The intensity of diffusive soft X-rays for specific multilayered systems consisting of two components is compared with the intensity of Cherenkov radiation. For radiation at photon energy of $99.4eV$, the intensity of Resonant Diffusive Radiation (RDR) generated by $5MeV$ electrons passing a $Be/Si$ multilayer exceeds the intensity of Cherenkov radiation by a factor of $\approx 60$ for electrons with the same energy passing a $Si$ foil. For a photon energy of $453eV$ and $13MeV$ electrons passing $Be/Ti$ multilayer generate RDR exceeding Cherenkov radiation generated by electrons passing a $Ti$ foils by a factor $\approx 130$. 
Zh.S. Gevorkian and J.Verhoeven