Construction and performance of one- and two-dimensional large position-sensitive liquid and plastic scintillation detectors - an application to a neutron polarimeter

Large one- and two-dimensional position-sensitive neutron detectors have been developed. Their shapes are a long block and a square and their sizes are 100×10×7.5 cm³ and 100×100×10 cm³ for one- and two-dimensional detectors, respectively. Both liquid and plastic scintillators are employed as detector materials. Position resolutions are examined by using monoenergetic neutron beams with energies of 61.6 MeV. The obtained position resolutions in FWHM are 3-5 cm and 4-14 cm for one- and two-dimensional detectors, respectively. Position resolutions are poor near the corner of the two-dimensional detector irrespective of scintillator materials. Scintillation light responses have been compared with predictions of Monte Carlo calculations. Neutron polarimeters at an intermediate energy have been developed by utilizing the position sensitivity of these detectors.