rf-Induced Sidebands in Mössbauer Spectra

We report the first clear evidence that rf magnetic fields generate acoustical side-bands in the Mössbauer spectra of metallic ${\mathrm{Fe}}^{57}$. We advance an explanation of this magnetoacoustic effect in terms of magnetostriction, and suggest that this effect provides a consistent explanation of the results of several earlier workers who observed rf resonance effects seemingly associated with hyperfine transitions.