Speaker
Description
The Fast Loading User Facility for Fission Yields (FLUFFY) has been used to measured short-lived fission yields on 238U and 239Pu via cyclical neutron activation analysis. Sub-second transport times allow FLUFFY to observe gamma-ray signatures from fission products with half-lives of less than one second. This ability makes it possible to report multiple independent fission product yields within a given mass chain. In addition to this experimental capability, a new analysis method for fission product yield determination has been developed. This method uses the Fission Induced Electromagnetic Response (FIER) code as a model for fission product gamma-ray emission in a chi-squared minimization. This method allows fission product yields to be determined simultaneously with nuclear decay properties, enabling investigations into uncertainties in the population of highly-excited states from high Q-value beta decays (e.g., the “Pandemonium”). A discussion of results from recent FLUFFY experiments is presented along with plans for future work.
This work was performed under the auspices of the U.S. Department of Energy (DOE) by Lawrence Berkeley National Laboratory under Contract DE-AC02-05CH11231 and the Office of Nonproliferation Research and Development (NNSA/NA-22) through the Nuclear Data Interagency Working Group program.