Experiments and possibilities with super-intense Mössbauer sources

Abstract

We have been able to prepare Mossbauer sources having intensities ranging from 10 to 100 Ci for several isotopes, using the Missouri University Research Reactor Facility, MURR. These sources offer rich opportunities for carrying out precision Mossbauer experiments as well as high collimation scattering experiments. Using such intense sources, we have been able to measure the interference parameter of the 46.5 keV Mossbauer transition to about 1% accuracy. We find it to be about 10% greater than predicted by theory, which may have significant implications for time reversal violation experiments. We have also been able to show that the Bragg scattered recoilless fraction scattered from (200) planes of sodium chloride crystals is 94% of that found for the (600) reflection, even though the integrated intensity of this reflection is more than a factor of 10 less than that of the (200) reflection. We highlight some of the experiments that we have carried out and discuss some of the enticing possibilities for the future with sources in the 10–1000 Ci range. One of these is the possibility of doing Mossbauer spectroscopy with a stationary source and absorber, moving only a monochromating crystal filter along the direction of the reciprocal lattice vector associated with the Bragg reflection being used.