Validation of gamma ray detector’s model for safeguards application

Abstract EN

Gamma ray spectrometry (NaI) is characterized in this work for safeguards application.

The manufacturer data and other data from X ray imaging are used to characterize and construct a detector model in conjunction with MCNP code.

The Monte Carlo method was used to calculate the photon detection efficiency for a 3"X3" NaI detector exposed to gamma ray with energy 661.7 keV at various distances for validation of the detector model.

The results that have been obtained by MCNP detector model are compared with the experimental results.

An agreement was found between calculated and experimental results of detector efficiency with accuracy ranging from -1.02947 % to 1.49405 %, which confirms the validity of the detector model.

The detector’s model developed with MCNP has been applied in order to calculate 235U mass in nuclear material (NM) samples for safeguards application.

Both the experimental results obtained as well as the MCNP results are used to estimate the 235U mass content.

The estimated 235U masses for NM samples are found to be in agreement with the declared values with an accuracy ranging from -0.539 % to 1.79 %.