Geant4 simulation of 238U(n,f) reaction induced by D-T neutron source

Cumulative fission yield measurements with 14.7 MeV neutrons on 238U*

“…As H. Naik showed, the mass chain yields could be obtained from the fission product yields by using a charge distribution correction [4]. However, the difference between the cumulative fission and the mass chain yields is much less than 1%.…”

“…The irradiation time of the U-1 sample was 60 min for the measurement of fission product nuclei with a lifetime of a few hours. To measure longer-lived fission product nuclei, the U-2 sample was irradiated for 17 h. The T(d, n) 4 He reaction with a deuteron beam (250 keV, 180 μA) produced 14 MeV neutrons. The energies of neutrons were measured using the cross-section ratio of 93 Nb(n, 2n) 92m Nb to 90 Zr(n, 2n) 89 Zr reaction and compared with results of mean neutron energy calculation [20,21], which were 14.7 ± 0.2 at 35°.…”

“…The energies of neutrons were measured using the cross-section ratio of 93 Nb(n, 2n) 92m Nb to 90 Zr(n, 2n) 89 Zr reaction and compared with results of mean neutron energy calculation [20,21], which were 14.7 ± 0.2 at 35°. The Au-Si detector relative to the deuteron beam at 135° monitored the accompanying 4 He particle to measure the neutron yield and neutron flux per 10 s, which would give a correction for neutron fluctuation.…”

“…The number of detected γ-rays corresponding to the activity of fission products was obtained from their total peak areas by subtracting the linear Compton background. The number of detected γ-rays under the photopeak of an individual fission product is related to their cumulative yields as follows [4]:…”

“…Detailed data on the fission cross section, fission-fragment mass, kinetic energy distributions, fission neutron spectrum, and γ-ray spectrum are urgently needed for generation-IV reactor modeling of fuel inventory, reactor decay heat estimation in accident scenario modeling, nuclear material safeguard monitoring, and exploration of nuclear fission theory [3]. Because 238 U is associated with 235 U in a conventional reactor and with 239 Pu in a fast reactor, the fission product yields (FPYs) of 238 U at different neutron energies are important for both conventional and fast reactors [4,5]. With the development of a thorium uranium circulating reactor and a fast neutron breeder reactor, the knowledge of 238 U(n, f) fission reaction induced by a 14 MeV neutron is significant.…”