Radiation field calculation for maritime nuclear emergency

Source term estimation is the primary technology employed for decision-making during nuclear emergencies. Maritime nuclear accidents have the issue of the movement of radioactive source terms and detectors. In this paper, a technical solution is proposed for the source term inversion of a marine nuclear accident, which is based on the time-spatial correction of the Gaussian cloud model and ensemble Kalman filter. Radionuclide concentrations at different positions under the Daya Bay nuclear power plant were incorporated for modeling a hypothetical nuclear accident, and the nuclear accident source strength was thereby obtained through the modified inversion method. The obtained result is found to differ from the hypothetical accident source strength by a margin of 18.4%. (authors)