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arXiv · 2403.07024

A polynomial chaos approach for uncertainty quantification of Monte Carlo transport codes

Gianluca Geraci·Kayla Clements·Aaron J Olson
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Abstract

In this contribution, we discuss the construction of Polynomial Chaos surrogates for Monte Carlo radiation transport applications via non-intrusive spectral projection. This contribution focuses on improvements with respect to the approach that we previously introduced in previous work. We focus on understanding the impact of re-sampling cost on the algorithm performance and provide algorithm refinements, which allow to obtain unbiased estimators for the variance, estimate the PC variability due to limited samples, and adapt the expansion. An attenuation-only test case is provided to illustrate and discuss the results.

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Gianluca Geraci, Kayla Clements, Aaron J Olson. 2024-03-10. A polynomial chaos approach for uncertainty quantification of Monte Carlo transport codes. https://arxiv.org/abs/2403.07024

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