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DOE OSTI · 1922063

Thermal Neutron Scattering Evaluation Methods Development at ORNL [Slides]

Chapman, Chris W.·Arbanas, Goran
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Abstract

The goal of the project was to develop a procedure to generate covariance matrix for S( α,β ) data that incorporated both computational simulations and experimental data. Experimental data and computer simulation fit is achieved using the Unified Monte Carlo (UMC) method. The framework is material & simulation method independent, and this is demonstrated using light water. A methodology was developed for generalized generation of covariances for thermal scattering files. The framework was subsequently tested on light water by generating covariance of pDOS with encouraging results. Preliminary results suggest temperature effects of polyethylene may warrant further investigation.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSEvaluated Nuclear Data File (ENDF)Molecular Dynamics (MD)National Energy Research Scientific Computing Center (NERSC)Nuclear Criticality Safety Program (NCSP)Nuclear DataPhonon Density of States (pDOS)Unified Monte Carlo (UMC)

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Chapman, Chris W., Arbanas, Goran. 2019-11-06. Thermal Neutron Scattering Evaluation Methods Development at ORNL [Slides]. https://doi.org/10.2172/1922063

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