Total Monte Carlo evaluation for dose calculations.

Area of Science:

• Nuclear physics
• Computational dosimetry
• Radiation transport

Background:

• Nuclear data (ND) uncertainties significantly impact radiation transport calculations.
• Traditional Total Monte Carlo (TMC) methods for uncertainty propagation are computationally intensive.
• Recent advancements have led to the development of fast TMC methods, increasing accessibility for complex applications.

Purpose of the Study:

• To evaluate the efficacy of the fast TMC methodology in a practical dosimetry scenario.
• To quantify the impact of (56)Fe nuclear data uncertainties on dose predictions for a 14-MeV neutron facility.
• To assess the generalizability of these findings to other dosimetry applications.

Main Methods:

• Implementation and testing of the fast TMC technique.
• Propagation of (56)Fe nuclear data uncertainties using multiple transport code runs with unique ND files.
• Calculation of dose distributions and their widths to represent uncertainty.

Main Results:

• The fast TMC methodology was successfully applied to a dosimetry problem.
• The uncertainty in the predicted dose outside the 14-MeV neutron facility due to (56)Fe nuclear data was determined to be 4.2%.
• The calculated uncertainty was found to be relatively small for this specific application.

Conclusions:

• Fast TMC is a viable and efficient method for propagating nuclear data uncertainties in dosimetry.
• While the (56)Fe uncertainty was small in this case, it underscores the importance of routinely considering ND uncertainties in dosimetry modeling.
• Further research is needed to generalize these findings across various dosimetry applications.