Investigating characteristics of neutrons from accelerator-driven compact source using novel target of compressed beryllium-powder

Abstract

The study was conducted at the cyclotron laboratory of the Tomsk Polytechnic University, on the use of a new form of target utilized in the production of fast-neutrons. The flux of fast-neutrons emitted by a novel target of beryllium powder compressed in a copper mold has been measured using Al and Fe foils as detectors. The change in the neutron flux in terms of the deuteron energy was studied by using thin aluminum filters. The increase of neutron flux reached about 60% when comparing with results obtained previously by our team when only the Be-target was used, this increase referred to the reaction Cu (n, 2n). In addition, comprehensive experimental graphs were obtained using our results beside other results from related literatures. It was found that they almost agree with the experimental results from the previous studies at energies less than 12 MeV, but then the neutron flux starts to increase when using a target of Be-powder compressed in a copper mold. The difference may become greater at energies above 15 MeV and the enhancement could be many times larger. Furthermore, fitted curves and their equations were obtained for the neutron flux as a function of deuteron-energy in the energy-range between 0.5 and 50 MeV. Also, the average energy of neutrons can be calculated from the derived equations for deuteron-ions in the energy-range from 2.6 to 40 MeV. The results of this study are new and promising, so that when confirming these results at higher energies above 15 MeV, we can obtain a greater neutron yield when using a target of Be-powder compressed in a copper mold or other metals with higher cross section of the reaction (n, 2n). The high intensity beams of fast-neutrons could be employed in many crucial applications, such as radiotherapy, production of radioactive isotopes, and more.