Development of High-Counting-Rate Neutron Detector for CP-Violation Search in Neutron-Induced Reactions

There is a need for a high-counting-rate neutron detector in order to search for CP-violations using compound nucleus resonances. A pixel-type detector based on a Li-glass scintillator, called the LiTA detector, is one candidate for this search. We measured the performance of this detector at MLF, J-PARC, and confirmed that it is usable up to a counting rate of 0.8 Mcps/cm^2. A boron-loaded liquid scintillator is another candidate for the high-counting-rate detector. The 3.7 ns decay time of this scintillator is shorter than that of the Li-glass scintillator. However, this liquid scintillator is sensitive to both neutrons and gamma rays. Pulse-shape analysis to remove the undesired gamma-ray signals was attempted.