On a characteristic feature of grazing-incidence nuclear monochromators for synchrotron radiation

Abstract

It is shown theoretically that the optimum resonance monochromatization of synchrotron radiation by means of grazing-incidence antireflection mirrors is obtained not at the maximum possible enrichment (∼100%) but rather with a low enrichment in the Mossbauer isotope (the natural abundance in the case of iron). This possibility is due to the fact that the conditions of interferometric suppression of electron reflection in the range of total external reflection angles is uniquely sensitive to small variations of the film or substrate density.