Fast Neutron–Induced Fission Cross Sections of ^{233, 234, 236, 238}U up to 200 MeV

Characterization of the Medley setup for measurements of neutron-induced fission cross sections at the GANIL-NFS facility

“…In the particular case of the ratio of fission cross sections 238 U/ 235 U , recent results from Refs. [2][3][4] are in quite good agreement up to 200 MeV with ENDF/B-VII, whereas results from [5] differ from them up to nearly 10%. Even more remarkable is that only a few experimental measurements have been done versus the H(n,p) scattering cross section (see Ref.…”

Measurement of the 234U(n,f) cross section in the energy range between 14.8 and 17.8 MeV using Micromegas detectors

“…5 During the irradiations, apart from the main energy neutrons, also some low energy ones exist in the neutron spectrum. Such neutrons, can also be called "parasitic" and may stem from break-up reactions, such as 3 H(d,np), 3 H(d,2n), 3 H(d,nd) etc, from reactions with 12 C nuclei ( 12 C(d,n)) that are present due to the carbon built up process, from reactions with the materials of the beam pipes (i. e 16 O(d,n), due to oxidization processes) and also from scattering in the materials of the whole experimental area. In order to determine the ratio: = 6P2 , which is necessary in order to correct for the low energy parasitic neutrons contribution in the fission yield, the simulated flux over the whole energy range was needed.…”

“…Concerning the experimental data for the 234 U(n,f) cross section, several datasets exist in literature, however, for neutron energies between 14 and 18 MeV, there are only 7 datasets [3][4][5][6][7][8][9] that present significant discrepancies (12-60%). Therefore, the purpose of this work was to lessen the aforementioned discrepancies and apart from that, to complete the meauserements of the 234 U(n,f) reaction over a wide energy range by combining the present project with two previous ones published by A. Tsinganis et al [10] and A. Stamatopoulos et al [11].…”

Neutron-induced fission cross-section measurement of 234U with quasi-monoenergetic beams in the keV and MeV range using micromegas detectors

“…The quasi-monoenergetic neutron beams in the MeV region were produced via the 2 H(d,n) 3 He reaction by bombarding a deuterium gas target with deuteron ions. The 3.7 cm long gas target is fitted with a 5 µm molybdenum entrance foil and a 1 mm platinum beam stop and is constantly cooled with a cold air jet during irradiation to diminish the risk of damage to the Mo foil.…”

“…There are a number of previous measurements of this cross-section in the energy ranges studied in this work, most of them performed several decades ago. More recently, three time-of-flight measurements have been performed by Paradela et al [1] and Karadimos et al [2] at the CERN n TOF facility and by Tovesson et al [3] at LANSCE (Los Alamos). These three measurements are in overall good agreement with each other, although the a e-mail: Andrea.Tsinganis@cern.ch data by Karadimos are systematically higher in the energy range between 0.5-1.0 MeV.…”