Gamma-Ray Output Spectra from $^{239}$Pu Fission

A new measurement of the gamma-ray energy spectrum and multiplicity following neutron-induced fission of $^{239}$Pu has been made using DANCE, a highly-segmented, nearly 4$\pi $ BaF$_{2}$ array at the Los Alamos Neutron Science Center. The $^{239}$Pu target consisted of an approximately 2 mg/cm$^{2}$ deposit mounted in a small parallel-plate avalanche chamber inserted into the DANCE in order to tag fission events. The gamma-ray spectra were measured for several strong neutron resonances below 100 eV. The measured spectra were corrected for detector response by using simple parameterizations of the actual fission gamma-ray emission coupled with a GEANT model of the DANCE array.