Nuclear Science and Engineering / Volume 160 / Number 2 / October 2008 / Pages 200-206
The 236U(n,f) cross section has been measured in the energy range from 0.5 eV to 25 keV at the Geel Electron Linear Accelerator neutron time-of-flight facility of the Institute for Reference Materials and Measurements in Geel, Belgium. A highly enriched 236U sample was mounted back-to-back with a 10B sample in the center of a Frisch-gridded ionization chamber, hence realizing a 2 detection geometry. A 235U(n,f) cross-section control measurement was performed in the same experimental conditions. Special attention has been given to the fission resonance integral If and to the strongest resonance at 5.45 eV, for which a resonance analysis has been performed yielding f = 1.7 eV. Both values are highly overestimated in the literature.