Determination of Neutron Yield from ‘‘THICK’’ Be Target Irradiated with 21.5 MeV Protons Using a Proton Beam Monitoring System

Abstract

The results of determining the neutron yield of the NS-21M facility, based on the I-2 linear proton accelerator and 3.8 mm thick Be target under bombardment by 21.5 MeV protons, are presented. This value was obtained by calculating the integral neutron flux passing through the front hemisphere at a specified distance from the center of the Be target relative to the average proton flux transmitted through a collimator of defined diameter. The experimental value of this quantity is \(Y_{n}^{{\textrm{exp}}}=(1.35\pm 0.09)\times 10^{-2}\), while the calculated value \(Y_{n}^{{\textrm{calc}}}=1.18\times 10^{-2}\) was derived by simulating the full mathematical model of the NS-21M stand using the PHITS-3.31 transport code. For 21.2 MeV protons, reaction cross-sections of \({}^{\textrm{nat}}\textrm{Cu}(p,x){}^{61}\)Cu, \({}^{62}\)Cu, and \({}^{64}\)Cu were determined using the monitor reactions \({}^{\textrm{nat}}\textrm{Cu}(p,x){}^{62}\)Zn and \({}^{\textrm{nat}}\textrm{Cu}(p,x){}^{63}\)Zn. Simulated excitation functions for these reactions (TENDL-2023, JENDL-5, PADF-2, and PHITS-3.31 with the INCL model) were plotted over the 0.01–3 GeV range alongside experimental data from EXFOR.