Adjoint-Based Uncertainty Quantification with MCNP

Abstract

This work serves to quantify the instantaneous uncertainties in neutron transport simulations born from nuclear data and statistical counting uncertainties. Perturbation and adjoint theories are used to derive implicit sensitivity expressions. These expressions are transformed into forms that are convenient for construction with MCNP6, creating the ability to perform adjoint-based uncertainty quantification with MCNP6. These new tools are exercised on the depleted-uranium hybrid LIFE blanket, quantifying its sensitivities and uncertainties to important figures of merit. Overall, these uncertainty estimates are small (< 2%). Having quantified the sensitivities and uncertainties, physical understanding of the system is gained and some confidence in the simulation is acquired.Professor Per F Peterson, Chair Date 1 AcknowledgementsLila Chase for assisting in compiling CRSRD, providing MCNP6 source code and compile advice, and squashing a strange bug in MAKXSF. John Wagner for providing the source for his code CRSRD.