Energy spectra of primary knock-on atoms under neutron irradiation

Bibliographic Details
Title: Energy spectra of primary knock-on atoms under neutron irradiation
Authors: Gilbert, Mark R., Marian, Jaime, Sublet, Jean-Christophe
Publication Year: 2015
Collection: Condensed Matter
Subject Terms: Condensed Matter - Materials Science
More Details: Materials subjected to neutron irradiation will suffer from a build-up of damage caused by the displacement cascades initiated by nuclear reactions. Previously, the main "measure" of this damage accumulation has been through the displacements per atom (dpa) index. There are known limitations associated with the dpa quantity and its domain of application and therefore this paper describes a more rigorous methodology to calculate the primary atomic recoil events (often called the primary knock-on atoms or PKAs) that lead to cascade damage events as a function of energy and recoiling species for any simulated or measured neutron irradiation scenario. Via examples of fusion relevant materials, it is shown that the PKA spectra can be complex, involving many different recoiling species, potentially differing in both proton and neutron number from the original target nuclei, including high energy recoils of light emitted particles such as alpha-particles and protons. The variations in PKA spectra as a function of time, neutron field, and material are explored. Example PKA spectra are applied to radiation damage quantification using the binary collision approximation and stochastic cluster dynamics, and the results from these different approaches are discussed and compared.
Comment: 27 pages, 12 numbers figures
Document Type: Working Paper
DOI: 10.1016/j.jnucmat.2015.09.023
Access URL: http://arxiv.org/abs/1506.08554
Accession Number: edsarx.1506.08554
Database: arXiv
More Details
DOI:10.1016/j.jnucmat.2015.09.023