A new neutron detector with a high position resolution for the study of the (p, pn) reaction on rare isotopes

We are developing a neutron detector with a position resolution better than 3 mm to study the single particle properties of nuclei by the knockout (p, pn) reaction at intermediate energies. We constructed a prototype detector consisting of scintillating fibers and multi-anode photomultiplier tubes (PMTs). A test experiment using 70-MeV proton and 68- and 50-MeV neutron was performed for characterizing its performance. In preliminary results, a position resolution of about 3 mm, is realized, as designed. The resulting separation-energy resolution would be 1 MeV, when using this system at a distance of 2 m from the target for measuring the (p, pn) reaction.