High precision gamma-ray energy measurements of fission products

Abstract Curved crystal spectrometers have been used to obtain high-precision γ-ray energies below 1 MeV of fission product lines arising from neutron capture in 235 U and 239 Pu produced in in-pile targets of 234 U and 238 U, respectively. Assignments of these γ-transitions to fission isotopes have been made.