Validation of MCNPX-PoliMi code for simulations of radioxenon beta–gamma coincidence detection

Radioxenon detection is an important component of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty. We developed and validated a new model in MCNPX-PoliMi to simulate the decay of various radioxenon isotopes and the detector response of a variety of detector types. The model was validated using calibration data from a plastic and NaI(Tl) beta–gamma coincidence detector and the results are presented. The results of this validation show that this model can also be used as a tool to produce training spectra and as a method to calibrate radioxenon detection systems