Pulse shape discrimination by use of a phoswich detector for high energy recoil proton detection

Abstract

Intermediate-energy proton accelerators are applicable to such facilities as an accelerator-driven subcritical system for long-lived nuclear-waste transmutation, and a proton beam cancer therapy. For the shielding and the target design of these facilities, nuclear data such as neutron-production double-differential cross sections are required. Since the experimental data in the intermediate-energy region are scarce, calculation codes based on the nuclear reaction model are used for the engineering purposes. To validate and improve the accuracy of the codes, further experiments are desired. The cross section of the continuous incident energy (n, xn) reaction was measured at the WNR in Los Alamos Neutron Science Center (LANSCE). Since the WNR is very strong neutron source, the neutrons under high background radiation environment had to be measured. For this reason, the recoil proton method was adopted and the recoil proton was detected by use of a phoswich detector composed of NaI(Tl) and NEI02A scintillators. The purpose of this study is to discriminate the full stop proton events from the background and partial energy deposition events.