Performance of a micro-TPC for a time-resolved neutron PSD

We report on the performance of a micro-TPC with a micro pixel chamber (μ-PIC) readout for a time-resolved neutron position-sensitive detector (PSD). Three-dimensional tracks and the Bragg curves of protons with energies of around 1 MeV were clearly detected by the micro-TPC. More than 95% of gamma-rays of 511 keV were found to be discriminated by simple analysis. Simulation studies showed that the total track length of proton and triton emitted from the 3He(n,p(573 keV))3H(191 keV) reaction is about 1.2 cm, and that both particles have large energy losses (>200 keV/cm) in 1 atm Ar+C2H6(10%)+3He(<1%). These values suit the current performance of the micro-TPC, and we conclude that a time-resolved neutron PSD with spatial resolution of sub-millimeters shall be developed as an application of the micro-TPC.