A Position-sensitive tubular scintillator-based detector as an alternative to a He-gas-based detector for neutron-scattering instruments

Nakamura, Tatsuya  ; Katagiri, Masaki*; To, Kentaro  ; Honda, Katsunori; Suzuki, Hiroyuki; Ebine, Masumi ; Birumachi, Atsushi; Sakasai, Kaoru  ; Soyama, Kazuhiko  

A position-sensitive tubular scintillator-based neutron detector is proposed as an alternative to a He-gas-based detector. The detector has a neutron-detecting element constructed from rolled ZnS/LiF scintillator screens that sandwich wavelength-shifting (WLS) fibre coils (SFC element). Multiple SFC elements are enclosed in an aluminium tube in a row to form a one-dimensional position-sensitive neutron detector. The design of the WLS fibre coil, which was determined by performing basic experiments, comprised two 0.75-mm-diameter WLS fibres wound in parallel at a pitch of 1.5 mm. A 64-element detector with a pixel size of 22 mm 20 mm (width length) successfully demonstrated the detection principle. The tubular shape of the new detector is similar to the usual 25-mm-diameter He tube, making this an alternative detector with the potential to be installed in a vacuum tank for inelastic-neutron-scattering instruments.