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

¹ State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
² Sate Key Laboratory of Particle Detection and Electronics
³ Institute of High Energy Physics, Chinse Academy of Sciences (CAS), Beijing 100049, China
⁴ Spallation Neutron Science Center, Dongguan 523803, China
⁵ Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China
⁶ Key Laboratory of Nuclear Data, China Institute of Atomic Energy, Beijing 102413, China
⁷ Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, China
⁸ Northwest Institute of Nuclear Technology, Xian 710024, China
⁹ University of Chinese Academy of Sciences, Beijing 100049, China
¹⁰ Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei 230026, China
¹¹ Beihang University, Beijing 100083, China

^* e-mail: guohuizhang@pku.edu.cn

Published online: 30 September 2020

Abstract

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 E_n > 20 MeV, the experimental results for both reactions are scarce with large uncertainties and discrepancies in general. For E_n ≤ 20 MeV, the experimental results lack systematicness, most of which were measured around E_n = 14 MeV even though the differential cross sections of n-p scattering in 1 keV ≤ E_n ≤ 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.