Shift of relaxation-stimulated resonances in Mossbauer absortion spectra in a static magnetic field

New features are obtained for previously predicted relaxation-stimulated re sonances in Mossbauer spectra of nanomagnets exposed to an external rf fiel d: the resonances should undergo low-frequency shift upon applying a weak s tatic magnetic field. Analytic expressions for the resonance frequencies as functions of the static field are obtained within a simplified relaxation model. This effect extends the possibilities for experimental observation o f the predicted effects, because tuning to the resonance may be accomplishe d not only by changing frequency of the rf field but also by varying the am plitude of the alternating field and the strength of the static field. (C) 2001 MAIK "Nauka/ Interperiodica".