The photofission cross section of U was measured at sub-barrier energies as a function of the -ray energy using a monochromatic, high-brilliance, Compton-backscattered -ray beam. The experiment was performed at the High Intensity -ray Source (HIS) facility at beam energies between MeV and 6.0 MeV and with energy resolution. Indications of transmission resonances have been observed at -ray beam energies of MeV and 5.6 MeV with moderate amplitudes. The triple-humped fission barrier parameters of U have been determined by fitting empire-3.1 nuclear reaction code calculations to the experimental photofission cross section.
- Received 10 February 2013
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