Secondary Radiation Field Effects for the CEM Spectra

The secondary resonant radiation field and resonant absorption thickness effects on the Conversion Electron Mössbauer Spectroscopy spectra are analyzed for highly enriched resonant targets. It is shown that secondary field effect is important for the thick α-Fe foil enriched in the resonant isotope. Even for the polycrystalline sample traces of the coherent resonant field have been detected as the distortion of lines. Secondary field is discussed in detail. Suitable approximations to treat spectra originating from targets with significant resonant thickness developing secondary field composed of the incoherent and coherent parts are introduced. Finally, the formalism is applied to the high quality spectrum recorded for the enriched iron foil and correlation between contribution due to the secondary field and experimental line shape is investigated.