Implementation of the RESKR module in NJOY

The Blackshaw-Murray[1] elastic kernel represents the effect of neutron up -scattering caused by thermal motion of target nuclei and resonance elastic scattering on the multigroup scattering matrices. A first implementation of this model was proposed by Ouisloumen and Sanchez and made available in proprietary cross -sections libraries of the PARAGON and APOLLO lattice codes.[2] Later, the same technique was reimplemented as module RESK in the NECP-Atlas cross-section generating code by J. Xu, T. Zu and L. Cao.[3, 4] The proposed RESKR module in NJOY-2012 and NJOY-2016 is based on the implementation of module RESK in the NECP-Atlas cross-section generating code.[5] The RESKR module is released under the BSD Open-Source license.