Total kinetic energy and mass yields from the fast neutron-induced fission of ${}^{239}$Pu

Abstract

The total kinetic energy (TKE) release in fission is an important observable, constituting over 80% of the energy released in fission (E${}_f$ $\approx$ 200 MeV). While the TKE release in the ${}^{239}$Pu(n,f) reaction was previously measured up to 50 MeV incident neutron energy (E${}_n$), there were features in TKE release at the highest values of E${}_n$ that were puzzling. There was a marked flattening of TKE release from E${}_n$ = 30 to 50 MeV, in disagreement with the clearly decreasing TKE observed from E${}_n$ = 0.5 to 30 MeV. To verify and clarify this trend, TKE measurements at higher values of E${}_n$ were made. We present absolute measurements of TKE release in ${}^{239}$Pu(n,f) from E${}_n$ = 2.4 to 100 MeV. We used silicon PIN detectors to measure the fragment energies and deduce mass-yield curves using the 2E-method. We also discuss fission asymmetry and the relationships between approximate fission fragment mass and distortion.

13 pages, Submitted to European Physical Journal A

References in corpus (2)

• Total Prompt Energy Release in the Neutron-Induced Fission of 235-U, 238-U, and 239-Pu
• Calculated fission-fragment mass yields and average total kinetic energies of heavy and superheavy nuclei

Cited by in corpus (2)

• The fast neutron induced fission of ${}^{240}$Pu and ${}^{242}$Pu
• Instrumentation for correlated prompt $n$-$\gamma$ emission studies in coincidence with fission fragments