English

NJOY+NCrystal: an open-source tool for creating thermal neutron scattering libraries

Instrumentation and Detectors 2022-01-26 v2 Materials Science

Abstract

In this work we present NJOY+NCrystal, a tool to generate thermal neutron scattering libraries with support for coherent and incoherent elastic components for crystalline solid materials. This tool, which is a customized version of NJOY, was created by modifying the nuclear data processing program NJOY to call the thermal scattering software library NCrystal, and includes a proposed change in the ENDF-6 format to store both the coherent and incoherent elastic components. Necessary changes to enable this format in NJOY, as well as to sample it in the OpenMC Monte Carlo code, are detailed here. Examples of materials that are coherent-dominant, incoherent-dominant, and mixed elastic scatterers are presented, as well as the creation of novel libraries for MgH2_2 and MgD2_2, that are under consideration as advanced neutron reflectors in the HighNESS project at the European Spallation Source. NJOY+NCrystal simplifies greatly the process to generate thermal scattering libraries (TSL) and this is exemplified with 213 new and updated TSL evaluations.

Cite

@article{arxiv.2108.11737,
  title  = {NJOY+NCrystal: an open-source tool for creating thermal neutron scattering libraries},
  author = {Kemal Ramic and Jose Ignacio Marquez Damian and Thomas Kittelmann and Douglas D. Di Julio and Davide Campi and Marco Bernasconi and Giuseppe Gorini and Valentina Santoro},
  journal= {arXiv preprint arXiv:2108.11737},
  year   = {2022}
}
R2 v1 2026-06-24T05:26:22.825Z