Enabling PSD-capability for a High-density Channel Imager

Pulse shape discrimination (PSD) is crucial for nonproliferation and security applications, where fast neutrons need to be identified and measured in the presence of a strong gamma ray background. The traditional charge-integration based PSD method requires the storage and processing of hundreds of samples for each single pulse, which is time- and memory-consuming for high density channel applications. In this work, we explored the possibility of implementing PSD using a commercial ASIC that allows the user to adjust the pulse shaping time. We demonstrated that PSD can be achieved by by maximizing the difference between the pulse shaping circuit’s responses to neutron and gamma ray pulses.