Total Kinetic Energy and Mass Yield Curves from the Fast Neutron-Induced Fission of $^{\mathrm{239}}$Pu

The total kinetic energy (TKE) release in fission constitutes the bulk of the energy released (Q$_{\mathrm{f}} \quad \approx $ 200 MeV). While TKE release in the $^{\mathrm{239}}$Pu(n,f) reaction was previously measured from 0.5 to 50 MeV (Phys. Rev. C \textbf{94}, 034611 (2016)), the highest energies in the evolution of TKE(E$_{\mathrm{n}})$ were puzzling. Notably, there was a high incident neutron energy flattening of TKE from E$_{\mathrm{n}} \quad =$ 30 to 50 MeV, contra the clear trend of decreasing TKE observed in the range of 0 to 30 MeV. Presented herein are measurements of TKE in $^{\mathrm{239}}$Pu(n,f) from E$_{\mathrm{n}} \quad =$ 2.5 to 100 MeV using PIN detectors, mass-yield curves using the 2E-method, and discussions of the symmetric fission contribution to TKE at high energies.