Neutron-induced fission cross section ofU237

An 18.1-μg sample of ${}_{}{}^{237}{}_{}{}^{}\mathrm{U}$ (half-life 6.70 ± 0.02 day) was prepared and exposed to a neutron beam from the underground nuclear explosion Pommard. The neutron-induced fission cross section was measured from 43 to 1000 eV and from 0.1 to 2 MeV. A resonance analysis was attempted from 43 to 220 eV; resonance areas are reported. Both $0^{+}$ and $1^{+}$ seem to be present, with average spacing 3.5 eV. The cross section at 1 MeV is 1.0 ± 0.1 b; from 300-1000 eV, the cross section is 30% of that for ${}_{}{}^{239}{}_{}{}^{}\mathrm{Pu}$.