A kinematically complete, interdisciplinary, and co-institutional measurement of the ¹⁹F(α,n) cross section for nuclear safeguards science

Neutron production in (α,n) reactions

“…For ceramics, the majority of neutrons come from aluminium while small abundances of 17 O and 18 O give small fraction of neutrons visible at high energies (above 4 MeV). The curves labelled 'EMPIRE3.2.3 + Exp' shows the neutron spectra obtained with a combination of cross-sections from experimental data ( [36] for PTFE and [46] for ceramics) and EMPIRE3.2.3 calculations. The experimental data are used where available, replaced with EMPIRE3.2.3 calculations at higher energies.…”

“…Rows 'EMPIRE3.2.3 + Exp' include results obtained using cross-sections from measurements where available, replaced by EMPIRE3.2.3 calculations at higher energies. Given a large spread of experimental data for cross-sections, only one measurement was used for each isotope and these measurements were taken from: [36] for 19 F, [40] for 13 C, [52] for 14 N, [46] for 27 Al, [53] for 17 O and 18 O, [54] for 28 Si, [47] 29 Si and 30 Si, [55] for 50 Cr, [56] for 54 Fe, [57] for 55 Mn, [49] for 60 data is very large (larger than for calculated cross-sections in realistic models) and there is no obvious choice of the data set to use. Measurements of the cross-sections are usually limited to the total cross-sections and do not provide transition probabilities to various excited states (not to high excited states anyway) so the use of a model is unavoidable to obtain the correct neutron spectrum.…”

“…[29,30] without and with the DR contribution, respectively. The data for fluorine are taken from Wrean et al [32], Vukolov et al [33], Balakrishnan et al [34], Norman et al [35], Peters et al [36] and Gladun et al [37]. (Note that Ref.…”

Neutron production in (alpha, n) reactions

“…Rows 'EMPIRE3.2.3 + Exp' include results obtained using cross-sections from measurements where available, replaced by EMPIRE3.2.3 calculations at higher energies. Given a large spread of experimental data for cross-sections, only one measurement was used for each isotope and these measurements were taken from: [36] for 19 F, [40] for 13 C, [52] for 14 N, [46] for 27 Al, [53] for 17 O and 18 O, [54] for 28 Si, [47] 29 Si and 30 Si, [55] for 50 Cr, [56] for 54 Fe, [57] for 55 Mn, [49] for 60 Ni and 62 Ni, [58] for 64 Ni, [59] for 46 Ti and [60] for 48 Ti. Spontaneous fission is significant for 238 U only and is independent of the material with a neutron yield of 1.353 × 10 −11 n/g/s/ppb.…”

Performance of the Versatile Array of Neutron Detectors at Low Energy (VANDLE)

“…The background reduction attained by utilizing a recoil separator and tagging on heavy reaction products is necessary for most cases with radioactive beams, where the random room background can be significant compared to the desired reaction. Figure 20 shows a drawing of the curved mounts for the small VANDLE modules used for a couple 19 F(α,n) 22 Na experiments [49] and a couple (d,n) experiments still under analysis.…”