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Precise measurement under high counting rates has been a major challenge for γ -ray spectroscopy, where signals generally pile up with each other and their characteristic values are deeply coupled. An off-line pile-up pulse recovery algorithm based on template matching is developed for LaBr 3 scintillation detectors and has been applied to data from China Spallation Neutron Source (CSNS) Back-n white neutron beamline. As an improvement to the traditional Template Matching methods, the predetermined template shape is associated with pulse amplitudes, which is found crucial to achieve the best fitting results. Moreover, a universal strategy of setting the initial values of fitting allows to resolve signals that are separated in time by less than the characteristic rise time. Processing of simulated pulses demonstrates that the lower limit of interval to distinguish successive events is 10 ns, which is a significant improvement to the previous works. The algorithm performs well under a counting rate of 6 × 1 0 7 s−1, and is still effective up to 1 0 8 s−1. Analysis of experimental data indicates that this algorithm recovers over 98% count yield under a counting rates of no more than 4 × 1 0 6 s−1 in this work, providing a more reliable approach to deduce neutron-induced reaction cross sections. [ABSTRACT FROM AUTHOR]

Due to the shortage of the 3He gas and its rapidly increasing price, scintillator detectors, the advantages of which are high spatial resolution and capability of detection in real time, become widely used in many neutron instruments. In this work, a position-sensitive neutron detector consisting of a 6LiF/ZnS scintillation screen and a silicon photomultiplier array linked to a capacitive network to detect the positions of incident neutrons, is constructed and tested. To evaluate the detector performance, a series of neutron beam experiments with the detector prototype were performed in the BL20 at the China Spallation Neutron Source. The spatial resolution was measured, and the energy-selective neutron imaging and Bragg edge measurements of a 316L stainless steel sample were performed. A sub-millimeter spatial resolution could be obtained for the detector prototype under study. The detector with such a high spatial resolution is promising for applications in neutron scattering experimental installations, especially for neutron single-crystal diffractometers. [ABSTRACT FROM AUTHOR]