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The neutron-induced single event effect affects the reliability of electronic devices used in aircraft and ground nuclear facilities. With the progress of semiconductor technology, device feature sizes become smaller and more integrated, radiation sensitivity increases and neutron single event effects become more of an emphasis. To evaluate the performance of electronic devices against neutron single event effects, ground-based neutron irradiation experiments are the most commonly used method in China and abroad. The quasi-monoenergetic neutron is an important neutron source for studying the law and mechanism of the neutron single event effects. Meanwhile, through irradiation experiments with multi-energy neutron beam, the energy dependence curve of the neutron single event effect cross section can be obtained, which can be used to predict the error rate of electronic devices exposed to various neutron radiation environments. Systematic experimental studies of the energy dependence of the neutron single event effect cross section have not been carried out in China, mainly due to the fact that there are few neutron sources suitable for conducting neutron single event effect experiments in China, especially the long-term lack of quasi-monoenergetic neutron sources above 20 MeV. In recent years, with the gradual completion and commissioning of several medium- and high-energy proton accelerators in China, quasi-monoenergetic neutron experimental research has become increasingly available. Theoretical simulation studies prior to the implementation of experimental studies. Based on the nuclear reaction theory, the secondary neutron yield and the neutron single energy peak yield were studied with 50-500 MeV proton and lithium bombardment. The trend of lithium target thickness was calculated by SRIM software with 1.3 MeV proton energy loss in lithium target. The thickness of lithium target with proton energy loss of 2 MeV, secondary neutron yield and neutron energy spectrum in different emission directions were simulated by Monte Carlo method for 50-500 MeV proton. The simulation results show that quasi-monoenergetic neutrons in 0° direction have the best monochromaticity, the neutron fluence rate can reach 104-105 cm-2·s-1 and the proportion of single energy peak is about 50%, for the position of 5 m from the Li target, when the proton intensity is 1 μA and the target thickness is 2 MeV proton energy loss, which can meet the research requirements of neutron single event effect. In conclusion, this work provides theoretical guidance for the design of quasi-monoenergetic neutron targets, beamlines and experimental terminals for neutron single event effect experiments, as well as for the implementation of neutron single event effect irradiation experiments.

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The cross sections of the 27Al(n,α)24Na and 27Al(n,p)27Mg reactions with the average neutron energies of 15.2, 26.4, and 37.2 MeV were measured using the activation and off-line γ-ray spectrometric technique at the Korean Institute of Radiological and Medical Sciences (KIRAMS), Korea. Quasi-monoenergetic neutrons produced via the 9Be(p,n) reaction with the proton beam energies of 25, 35, and 45 MeV from the MC50 cyclotron of KIRAMS were used. The present measured values were compared with those from the evaluated nuclear data libraries ENDF/B-VII, TENDL-2015, TALYS 1.8, and from literature. In general, a close agreement with the literature data as well as the evaluated data was found. [ABSTRACT FROM AUTHOR]

Au, Bi, Co and Nb samples were irradiated several times with quasi-monoenergetic neutrons from p + 7 Li reaction in the energy range of 18–36 MeV. The activities of the samples were measured with the HPGe detector and the reaction rates were calculated. The cross-sections were extracted using the SAND-II method with the reference cross-sections from the EAF-2010 database. The uncertainties of the final results are discussed. [ABSTRACT FROM AUTHOR]

We present cross section measurements for neutron-induced activation of Bi, at 287 and 370 MeV. These values were derived from the activation method using a quasi-monoenergetic neutron field based on the 7Li(p, n) reaction. In separate experiments, samples were irradiated with neutrons derived from 7Li(p,n) reaction at either 0° or 30° for proton beam axis. This approach allows the subtraction of the low energy neutron components. The measured cross sections are compared with the findings of other studies, and evaluated in relation to nuclear data files. [ABSTRACT FROM AUTHOR]

Abstract: Angular differential neutron elastic scattering cross sections have been measured by using a 7Li(p,n) quasi-monoenergetic neutron beam. The neutron beam whose peak energy is 134 MeV was incident upon a natural carbon sample, and the scattering neutrons were measured by liquid organic scintillators with the time-of-flight (TOF) technique. The results were compared with the existing experimental data measured by a recoil-proton telescope, and the evaluated nuclear data of JENDL/HE-2007 and ENDF/B-VII.0. [ABSTRACT FROM AUTHOR]

Abstract: The neutron response functions of 12.7cm diameter by 12.7cm long NE213 organic liquid scintillator have been measured in the energy range up to 390MeV at the Research Center for Nuclear Physics (RCNP) of Osaka University. The continuous energy neutrons were produced by the 392MeV proton bombardment on a 20-cm thick aluminum target and the response functions of the time-of-flight (TOF)-gated monoenergetic neutrons in a wide energy range up to 390MeV were simultaneously measured. The quasi-monoenergetic neutrons were also produced via 7Li(p,n)7Be reaction by the 392-MeV proton beam bombardment on a 1.0-cm thick 7Li target, and the TOF-gated 388-MeV peak neutrons were used to obtain the response function at this energy. The measured results show that the response functions for monoenergetic neutrons below 100MeV have a recoil proton plateau and an edge around the maximum light output which increases with increasing neutron energy, while on the other hand, for energies above 100 MeV, the plateau and the edge become unclear because the proton range starts to exceed the detector size allowing protons to escape. [Copyright &y& Elsevier]