The resonance absorption integral of 238U

Abstract

The resonance absorption integral of infinitely diluted ²³⁸U is calculated between the first resolved level (6·7 eV) and I MeV. The energy-independent parameters Γ_n⁰/D and Γ_γ/Γ_n⁰ of the average absorption cross-section are determined from the region of resolved resonances and the nuclear model theories, The effect of l > 0 neutrons is shown to be small but significant. The total value of 277 ± 10 per cent barns is in good agreement with experiment.