Neutron detection systems are widely used for nuclear material control and accounting. One focus for such systems is to accurately quantify the fissile material in unknown samples by means of non-intrusive methods. Neutron multiplicity counting (NMC) techniques are implemented for fissile mass estimation, which involves detecting neutrons that are correlated in time. NMC traditionally relies on capture-based detectors (i.e. 3~He detectors), however there has recently been an interest in systems that utilize alternative detectors such as organic scintillators. These scintillator-based multiplicity counters can potentially relieve the dependence on 3~He while also exhibiting additional capabilities due to the absence of moderating material between the sample and the detector array. Specifically, characteristic properties of the sample, such as neutron anisotropy and energy spectra can be measured. Furthermore, the time-scale of typical scintillator-based systems is on the order of tens of nanoseconds. Fast timing allows for detection of higher-order multiplicities with a much lower rate of accidental correlations.
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