2025/02/01 by P. Talou, Talou, Patrick, A. E. Lovell +9
Physics and Astronomy · Medicine · #Nuclear physics research studies #Medical Imaging Techniques and Applications
paper · pdf · doi:10.48550/arxiv.2502.00599
We investigate the time evolution of prompt fission γ emission due to the presence of ns to ms isomers in the fragments produced in the neutron-induced fission of 233,235U and in the spontaneous fission of 252Cf. Calculations performed with the CGMF fission event generator are compared with recent experimental data on 252Cf(sf) and 235U(n,f) obtained with the DANCE+NEUANCE setup at the Los Alamos Neutron Science Center. Of particular interest are the average γ-ray energy spectrum as a function of time since scission, ϕ(εγ,t), the increase of the average γ-ray multiplicity over time, Nγ(t), and its evolution in time as a function of the fission fragment mass, Nγ(A,t). The time evolution of isomeric ratios in post-neutron emission fission fragments can be defined and used to test and reveal some deficiencies in our knowledge of the low-lying levels of neutron-rich nuclei produced in fission reactions.