A half-millimetre spatial resolution fibre-coded linear position-sensitive scintillator detector with wavelength-shifting fibre read-out for neutron detection

Abstract

A fibre-coded linear scintillator detector with a half-millimetre spatial resolution was developed with wavelength-shifting fibre read-out for neutron detection. The head of the detector comprised a ZnS/6LiF scintillator placed on the ribbon of wavelength-shifting (WLS) fibres. Both ends of the fibres were coded to reduce the number of read-out photomultipliers and associated electronic circuitry. The prototype detector in which the fibre ribbon was sandwiched between two ZnS/6LiF scintillators exhibited a spatial resolution of 0.5mm, a detection efficiency of 35% for 1-Å neutrons, and a gamma sensitivity of less than 10−7. This type of detector would be useful where a submillimetre spatial resolution is required with large detector coverage such as in neutron reflectometers.