FPGA Based Wide Range Neutron Flux Monitoring System Using Campbell Mode

Neutron flux monitoring in research reactors can range from shutdown to full power over 10 to 12 decades. At low power, neutron flux is usually measured with proportional counters in pulse mode. The detector is moved away from high flux zones to avoid pulse saturation until ionization chambers are in range. Campbell mode allows to make a measurement using a single detector able to cover the entire operating range. This work presents an FPGA-based system that implements Campbell mode operation. The system prototype was successfully tested in the CNEA RA-3 research and production reactor at Ezeiza Atomic Center.