Journal of physics-condensed matter vol:12 issue:5 pages:637-642
Using a resonant detector in Mossbauer spectroscopy can result in a spectral linewidth that is 1.46 Gamma, where Gamma is the linewidth of the excited-state nuclear level. As is well known, the minimum linewidth obtained in conventional Mossbauer experiments is 2 Gamma. The quantum mechanical calculation using a nuclear resonant detector, which predicts this result, is presented. The fundamental equations describing the system are solved by means of perturbation theory in the frequency domain. The model system is taken to consist of a source nucleus, an absorber nucleus, and the resonant-detector nucleus. As noted, the minimum linewidth obtained in a Mossbauer spectrum taken under these conditions is found to be appreciably smaller than the linewidth obtained in a conventional Mossbauer set-up. Thus the conversion-electron, resonant-detector scheme may be used to advantage in experiments requiring the highest possible energy resolution.