Real-Time Micro-Miniature Dosimeter

The new Presidential directive to place humans on Mars and establish bases on the moon will require advances in space nuclear power generation. Nuclear power generation has a combined advantage in power density, low fuel/mass ratio, mission duration and cost over any other generation method for these missions. To meet the needs of reactor safety, health monitoring and performance, light-weight, real-time, in-core neutron and gamma monitoring sensors need to be developed. Luna is proposing to further develop a real-time miniature gamma and neutron dosimeter. This hybrid sensor will measure gamma and neutron dose independently, as well as temperature at the same location. The transducer will be less than 5mm long and 1mg in mass. This dosimeter will enable real-time determination of reactor power level, health and remaining fuel as well as shielding effectiveness. During the Phase I, Luna demonstrated feasibility of the proposed dosimeter material systems in a nuclear reactor determining that minimum dosimeter resolutions (based on material measurements) of 0.57MRad gamma and 0.83x1014n/cm2 can be accomplished with EFPI based sensors. Phase II will optimize the sensor designs and demodulation system for performance and cost, considering space hardening constraints, and demonstrate the system in high radiation and high temperature environments.