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arXiv · 1403.4316

The Excitation Energy Dependence of the Total Kinetic Energy Release in 235U(n,f)

Abstract

The total kinetic energy release in the neutron induced fission of $^{235}$U was measured (using white spectrum neutrons from LANSCE) for neutron energies from E$_{n}$ = 3.2 to 50 MeV. In this energy range the average post-neutron total kinetic energy release drops from 167.4 $\pm$ 0.7 to 162.1 $\pm$ 0.8 MeV, exhibiting a local dip near the second chance fission threshold. The values and the slope of the TKE vs. E$_{n}$ agree with previous measurements but do disagree (in magnitude) with systematics. The variances of the TKE distributions are larger than expected and apart from structure near the second chance fission threshold, are invariant for the neutron energy range from 11 to 50 MeV. We also report the dependence of the total excitation energy in fission, TXE, on neutron energy.

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R. Yanez, L. Yao, J. King, W. Loveland, F. Tovesson, N. Fotiades. 2014-03-18. The Excitation Energy Dependence of the Total Kinetic Energy Release in 235U(n,f). https://doi.org/10.1103/physrevc.89.051604

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