Double-, energy-, angle- differential and total yield cross section data of 58Ni(n,a)55Fe reaction

The double-, energy-, angle- differential cross section data, and the total yield of 58Ni(n,α)55Fe reaction is investigated in the neutron energy range between 2 and 9 MeV. The measurements were performed with the prompt detection method, detecting the alpha particles of the reaction with a multitelescope consisted of five ΔΕ-ΔΕ-Ε telescopes, placed at angles 14, 51, 79, 109 and 141 degrees relative to the neutron beam direction. The normalisation to the absolute units was made using the known total yield of the reference reactions 27Al(n,α)24Na and 58N(n,p)58Co. The cross section measurements were compared with previous measurements and with theoretical calculations performed with the STAPRE-H [1-4] code.

Evaluation of neutron induced reactions on 56Fe with CONRAD

The evaluation of the 56Fe neutron induced reactions is currently ongoing at the CEA-Cadarache using the code CONRAD, with the goal to cover the whole energy range from the Resolved Resonance Region to the continuum and estimate the corresponding uncertainties and covariance matrices. Some first results and issues occurred from this work are presented and discussed here, more specifically on the analysed transmission and capture data in the Resolved Resonance Region, as well as the optical and statistical model calculations in the fast neutron energy range.

Angular distributions and anisotropy of fission fragments from neutron-induced fission of 239Pu, 237Np, and natPb in energy range 1–200 MeV

This work summarizes some results of a series of experiments aimed at the investigation of energy dependence of anisotropy of fission fragments (FFs) in (n, f) reactions for neutron energies from low to intermediate. Angular distributions of FFs from the neutron-induced fission of 239Pu, 237Np, and natPb have been measured in the energy range 1–200 MeV at the neutron TOF spectrometer GNEIS based on the spallation neutron source at 1 GeV proton synchrocyclotron of the Petersburg Nuclear Physics Institute (Gatchina, Russia). The anisotropies of FFs deduced from the measured angular distributions are presented. In the neutron energy range above 20 MeV the results have been obtained for the first time in our works. The experimental data for FF anisotropy in 237Np(n, f) are compared with calculations based on "adapted" TALYS software.

Simulations of the measurement results of differential cross sections of n-p and n-d elastic scattering at CSNS Back-n WNS

Differential cross-section data for the n-p and n-d elastic scattering (1H(n, el), 2H(n, el)) are collected and analyzed from EXFOR library. For En > 20 MeV, the experimental results for both reactions are scarce with large uncertainties and discrepancies in general. For En ≤ 20 MeV, the experimental results lack systematicness, most of which were measured around En = 14 MeV even though the differential cross sections of n-p scattering in 1 keV ≤ En ≤ 20 MeV region are recommended as standard. Taking these facts into account, more accurate and systematic measurements are planned. The experiments will be conducted using ΔE-E detectors of the Light-charged Particle Detector Array (LPDA) system at China Spallation Neutron Source (CSNS) Back-n White Neutron Source (WNS), and simulations are carried out. Using polyethylene and deuterated polyethylene as samples, both n-p and n-d scattering reactions are simulated along with the neutron-induced 12C background reactions, and the 2-D spectra and the counting rates of the ΔE-E detectors are obtained. According to the simulations, the applicable neutron energy range and positions of the detectors are recommended, and the beam time for the event and background measurements is suggested.