Nuclear Fluorescence Using High-energy Synchrotron Radiation

We present some measurements of nuclear fluorescence which were made while exploring the potential of a unique source of very hard x‐rays which was installed at ESRF until recently. It produced radiation of energies up to 1MeV. In this range there are many nuclear resonances, and so we made a small survey of some plausible candidates to see if they could indeed be excited using this source. Along with short‐lived resonances, we were also able to indirectly populate long‐lived isomeric states in several nuclei. Thus, simply exposing the samples to the white beam for a period of time caused them to be activated. The samples could them be removed from the beam and their emissions observed using an energy‐resolving detector. Isomeric states in isotopes of indium, cadmium and silver were excited and their subsequent decay observed.