Radiation Field Reconstruction Method Based on Non-uniform Source Activity Distribution Inversion

The accurate reconstruction of the gamma radiation field is the foundation for achieving digitalization of radiation protection and the prerequisite for conducting radiation dose assessment and visual simulation. In order to effectively solve the practical problem of large deviation in three-dimensional gamma radiation field reconstruction caused by high gradient non-uniform radiation source term distribution at nuclear facilities, this paper innovatively proposes a method for selecting non-uniform source activity distribution models based on Bayesian information criteria, and applies the optimal model to the reconstruction of three-dimensional gamma radiation fields. The results show that the accuracy of radiation field reconstruction using this method is significantly better than that of the Kriging interpolation method under high activity gradient and high dose rate gradient conditions; In the case of three-dimensional radiation field reconstruction in actual nuclear facilities, the average relative deviation between the dose rate reconstruction results of the test set and the measured values is only 12.69%, which is lower than the 85.40% obtained by Kriging interpolation. This study can provide advanced technical support for dynamic data-driven digital simulation of radiation protection in nuclear facilities, enhancing its effectiveness in practical applications.