A neutron spectrometer for small satellite opportunities

The detection of fast neutrons has important applications in a wide variety of fields including geospace, solar and planetary physics, and applications within Defense and Security programs. Scintillator-based technologies have a proven record for detecting and measuring fast neutrons. They have high stopping power, good energy resolution, and fast timing properties. Modern organic scintillators such as stilbene and p-terphenyl, provide improved light output and pulse shape discrimination the ability to distinguish gamma-from neutron-induced signals. Furthermore, modern readout devices such as silicon photomultipliers offer an ideal alternative to photomultiplier tubes given their inherently compact size and low operating voltages. The combination of modern scintillators and silicon photomultipliers enables new instrument designs for small satellite platforms such as CubeSats. We present the performance of a double-scatter neutron spectrometer based on p-terphenyl equipped with silicon photomultipliers. We also present preliminary results for pulse-shape discrimination using advanced waveform digitization techniques.