We compare deposition spectra from monoenergetic neutron irradiation to CUPID simulations of the same neutron exposures. CUPID does not agree with the experimental data unless pion production is included in the neutron-nucleon interaction. Pion-production events result in slightly more single-event effects (SEEs) for devices with relatively large sensitive volumes and low thresholds for upset but dramatically fewer events for the same sensitive volume when the threshold is high.

A portable, lower power, high energy neutron spectrometer is being developed to support long duration manned space missions. We report on the first phase which will select the most appropriate solid state system for neutron detection.