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

Yuki Kubota ,H Tokieda ,K Sekiguchi ,T Uesaka ,C S Lee ,Hiroaki Matsubara ,T L Tang ,M Dozono ,M Sasano ,Masatoshi Itoh ,Hiroyuki Miya ,S Ota ,Mariko Kobayashi ,Takahiro Taguchi ,S Kawase ,Takashi Wakui

doi:10.1051/epjconf/20146611022

Abstract

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.

Highlights

Nucleon-knockout (p, 2p), (p, pn) reactions at intermediate energies (200–300 MeV) provide a powerful probe of the single particle nature of nuclei[1]
We are developing a prototype detector as a new neutron detection system to achieve a position resolution better than 3 mm for neutrons with kinetic energies ranging from 50 to 200 MeV. This position resolution, when the detector is placed at a distance of 2 m from the target, corresponds to a separation energy resolution of 1 MeV, a reasonable resolution for distinguishing neighboring single particle states
We segmented a scintillator of 30 × 30 mm2 total cross section to an array of 64 plastic scintillators each with sizes of 3.75 × 3.75 mm2, so that we can see the trajectory of the proton as the hit pattern of the segments

Summary

Introduction

Nucleon-knockout (p, 2p), (p, pn) reactions at intermediate energies (200–300 MeV) provide a powerful probe of the single particle nature of nuclei[1]. Exclusive measurements of the (p, 2p), (p, pn) reactions allow one to determine the separation energies, becoming one of hot topics in studies of unstable nuclei. We are developing a prototype detector as a new neutron detection system to achieve a position resolution better than 3 mm for neutrons with kinetic energies ranging from 50 to 200 MeV. This position resolution, when the detector is placed at a distance of 2 m from the target, corresponds to a separation energy resolution of 1 MeV, a reasonable resolution for distinguishing neighboring single particle states

Prototype detector

Experiment

Results

Summary and outlook