A neutron detection apparatus includes a neutron detector and an analyzer. The neutron detector includes a plurality of neutron detector assemblies, where each of the neutron detector assemblies includes a plurality of neutron detection devices. The neutron detector also includes a moderating volume. The plurality of neutron detector assemblies are disposed within the moderating volume so as to form a three-dimensional array of neutron detection devices within the moderating volume. The analyzer is communicatively coupled to each of the neutron detection devices of the plurality of neutron detector assemblies. The analyzer configured to receive one or more measured response signals from each of the neutron detection devices, and perform one or more analysis procedures to determine one or more characteristics associated with the one or more neutron sources based at least on the received one or more measured response signals.