Neutron Fission Cross-Section Measurement of Americium-241 in the Energy Range from 10 to 1030 keV

The neutron fission cross section of 241Am was measured in the energy range from 10 to 1030 keV using 235U as a standard. The measurements were carried out at the Karlsruhe 3-MV pulsed Van de Graaff accelerator with 7Li targets for the generation of a continuous neutron spectrum below 140 keV and monoenergetic neutron spectra between 120 and 1030 keV. Fission events were detected by measuring the prompt fission neutrons with an NE-213 liquid scintillator with pulse-shape discrimination. The flight path was as short as 60 mm in measurements with continuous neutron spectra leading to a moderate energy resolution. The statistical uncertainty was between 0.8 and 10% and the systematic uncertainty between 5.4 and 8.5%. Discrepancies were found when comparing our results with those of other experiments.