Developing an 'atomic clock' for fission lifetime measurements

The relevance of measuring fission lifetimes of hot nuclei is briefly discussed. It is shown that K X-ray emission prior to fission can be used to measure fission lifetimes. The preparation of the K-shell hole, the simultaneous nuclear excitation, and the analysis of the X-ray spectra is described. First results of a measurement using a 20Ne beam of 30 MeV/nucleon on a 232Th target are reported