The Thermal Scattering Law Project

Harnessing modern methods for material modeling and high-fidelity thermal scattering evaluations, the Scattering Law Project provides access to nuclear thermal scattering data from fundamental inputs to benchmark testing on key reactor and nuclear criticality materials to inspire and support the next generation of nuclear applications.

Graphite – Crystalline

Graphite is a key moderating material which is vital to next generation advanced reactors, criticality safety, and reactor reflectors. Graphite was modelled using ab initio lattice dynamics (AILD) methods using the VASP and PHONON codes with the thermal scattering law (TSL) calculated using FLASSH 1.0.

Two evaluations have been completed for crystalline graphite: one under the cubic and incoherent approximations, one with full non-cubic treatment with one-phonon (Sd) corrections. The impact of the Sd treatment is primarily seen in the structure introduced to the TSL, and some impact is notable to the total cross section particularly below the Bragg cutoff, improving overall agreement with experimental data and allowing for direct benchmarking of both the TSL and cross sections.

Publications

Thermal Neutron Scattering Law Calculations using Ab Initio Molecular Dynamics
Advanced Methods of Thermal Neutron Scattering Analysis for Reactor Multi-Physics Applications
Benchmark of Neutron Thermalization in Graphite Using a Pulsed Slowing-Down-Time Experiment
Impact of the Graphite Thermal Scattering Law on Criticality Calculations
Benchmarking Thermal Neutron Scattering in Graphite
 

Download Data