Identification of Neutrons Using Digitized Waveforms

Abstract: The advantages of performing neutron-tagging measurements using a waveform digitizer are explored. An existing analog setup consisting of modular crate electronics at the Source-Testing Facility at the Division of Nuclear Physics in Lund, Sweden has been digitally replicated. Neutrons are detected using an organic liquid-scintillator detector while the corresponding 4.44 MeV gamma-rays are detected using inorganic scintillation crystals. The performance of the digitizer-based setup is compared to that of the modular analog setup in terms of neutron and gamma-ray pulse-shape discrimination and time-of-flight. The results obtained using the digitizer-based approach are superior to those obtained using the modular analog approach in all aspects. The digitizer-based approach is then successfully employed both to distinguish between neutrons and gamma-rays via a convolutional neural network and to relate neutron deposition energy to neutron kinetic energy via time-of-flight.