Development of NANA: A Fast-Scintillator, Coincidence Gamma-ray Array for Radioactive Source Characterisation and Absolute Activity Measurements at the UK National Physical Laboratory

Abstract

A multi-detector modular coincidence gamma-ray spectrometer is being designed and constructed for use at the UK's National Physical Laboratory (NPL) for use in direct measurement and metrological standardisation of nuclear decay activities. In its first generation, the NPL National Nuclear Array (NANA) will consist of twelve individual halide scintillation detectors placed in a high-efficiency geometry around a well-defined central point source position. This brief conference paper provides details of the measured detector module and coincidence energy and timing responses for the LaBr3(Ce) detectors which will be used in the NANA array. Preliminary GEANT4 simulations of the array's full energy peak efficiency and expected gamma-ray coincidence response are also presented.