Monte Carlo Simulation of Burnup Measurement of Spent Fuel Assembly by Using CdZnTe Detector System

The γ spectrum detecting system with CdZnTe (CZT) detector is one of effective methods for burnup measurement of spent fuel assembly. The detector efficiencies of the full energy peak for ¹³⁷Cs and ¹³⁴Cs were calculated with Geant4. The direction biasing sample method of source particle was used to improve calculation efficiency. The results provide a theoretical guide for the further burnup measurement.