Neutron Capture and Fission Measurement on $^{238}$Pu at DANCE
ORAL
Abstract
Neutron capture and fission reactions on actinides are important in nuclear engineering and physics. DANCE (Detector for Advanced Neutron Capture Measurement, LANL) combined with PPAC (avalanche technique based fission tagging detector, LLNL) were used to study the neutron capture reactions in $^{238}$Pu. Because of extreme spontaneous $\alpha$-radioactivity in $^{238}$Pu and associated safety issues, 3 separate experiments were performed in 2010-2012. The 1st measurement was done without fission tagging on a 396-$\mu$g thick target. The 2nd one was with PPAC on the same target. The 3rd final measurement was done on a thin target with a mass of 40 $\mu$g in order to reduce $\alpha$-background load on PPAC. This was the first such measurement in a laboratory environment. The absolute $^{238}$Pu(n,$\gamma$) cross section is presented together with the prompt $\gamma$-ray multiplicity in the $^{238}$Pu(n,f) reaction.
*This work was performed under the auspices of the US Department of Energy by Los Alamos National Laboratory under Contract DE-AC52-06NA25396 and Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
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