Development of secondary particles detection system with stilbene organic scintillator in J-PARC RCS

Yoshimoto, Masahiro; Okabe, Kota; Kinsho, Michikazu

no journal, , 

In the J-PARC RCS, 400 MeV H beams from the LINAC are injected to the stripper foils so that the most of beams are converted to protons. The stripper foil is irradiated not only by the injected H beams but also by the circulating protons. The high energy and intense beam irradiation into the foil generates secondary neutrons and protons via nuclear reactions. These secondary particles cause high residual activation around the stripper foil. To measure the secondary particles from the stripper foil, the particle detector system is required to discriminate among proton, neutrons and rays. Then, we develop the detector system combining a stilbene organic scintillator and a plastic scintillator. The stilbene scintillator can discriminate rays and other particles (protons and neutrons) with the Pulse Shape Discrimination (PSD) function. Furthermore, it can separate protons from neutrons by using the plastic scintillator which is set on the front of the stilbene scintillator. In this presentation, we report the PSD performance test of the stilbene scintillator in the utility tunnel in the RCS.