Prompt energy distribution of 235U(n,f)γγ at bombarding energies of 1–20 MeV

The distributions of prompt γγ rays from the spontaneous fission of 252Cf and neutron-induced fission of 235U were measured up to ∼4MeV using a liquid scintillator array. The unfolding of measured fission γγ rays is presented using the Single Value Decomposition and iterative Bayesian methods. General agreement was found with comparisons made with previous measurements. The energy dependence of the prompt γ-rayγ-ray distributions for the spontaneous fission of 252Cf and the neutron-induced fission of 235U from bombarding energies of 1-2, 5-10, and 10–20 MeV were found to be almost identical in the γ-rayγ-ray energy region 1–4 MeV.