Abstract
A variable-frequency 57Fe nuclear monochromator has been developed using a pure nuclear Bragg reflection from an oscillating 57FeBO3 single crystal at the Néel temperature. The Doppler-shifted single-line 57Fe Mössbauer radiation at a fixed beam position was successfully filtered using the third-generation synchrotron radiation (SR) of SPring-8. We describe the principle of the variable-frequency Mössbauer filtering technique, the study on the beam characteristics, and some demonstrative experiments on energy-domain SR Mössbauer spectroscopy.