A Submillimeter spatial resolution scintillation detector for time-of-flight neutron diffraction imaging

Nakamura, Tatsuya  ; Kawasaki, Takuro   ; To, Kentaro  ; Tsutsui, Noriaki; Ebine, Masumi ; Birumachi, Atsushi; Sakasai, Kaoru  

A two-dimensional scintillation neutron detector with a submillimeter spatial resolution was developed for pulsed neutron diffraction imaging at the J-PARC MLF. The detector comprised the thin, single ZnS/LiF scintillator screen coupled with the crossed wavelength-shifting fiber array for light collection. For a high spatial resolution, the wavelength shifting fibers with diameter of 0.1 mm were used them for assembling the detector. The prototype detector that has a neutron-sensitive area of 24 24 mm exhibited a spatial resolution of 0.200.06 mm and 0.160.06 mm for x and y directions, respectively. The detector had a detection efficiency of 7 for thermal neutrons with a Co -ray sensitivity in the order of 10. In this paper detailed detector design is presented together with experimental results using the pulsed neutron beam.