Citation:
D. Mulyana, S.S. Chirayath, “A Gamma Spectroscopy-Based Non-Destructive Approach for Pebble Bed Reactor Safeguards”, Annals of Nuclear Energy, 195 (2024).
Abstract:
A gamma radiation spectroscopy study was carried out for the nuclear safeguards monitoring of fuel burnup and special nuclear material (SNM) mass in the irradiated fuel of a pebble bed reactor (PBR). The concentration of radioactive materials in irradiated PBR fuel pebbles was estimated as a function of fuel burnup for varying 235U enrichments using the Monte Carlo N-Particle (MCNP) neutronics simulation code. Gamma radiation spectra corresponding to various pebble fuel burnups were then created using MCNP modeling and simulations of a high-purity germanium (HPGe) detector. Analysis of the simulation results showed that the correlations such as (a) fuel burnup versus over 235U content, total Pu content, 137Cs content, 134Cs/137Cs ratio, and 154Eu/137Cs ratio; (b) 137Cs mass versus over 235U content, total Pu content, and fissile Pu content, and (c) 134Cs/137Cs or 154Eu/137Cs ratio versus total Pu content are sufficient to estimate pebble fuel burnup and the SNM mass.