Title:	DAMAGE
DNr:	SNIC 2015/1-3
Project Type:	SNIC Medium Compute
Principal Investigator:	Janne Wallenius <janne@neutron.kth.se>
Affiliation:	Kungliga Tekniska högskolan
Duration:	2015-01-29 – 2016-02-01
Classification:	10304
Homepage:	http://neutron.kth.se/
Keywords:

Abstract

The nature of radiation - matter interactions is investigated in this project using quantum mechanical computer simulations for low energy interactions. We propose to study the effect of elastic collisions in a crystal lattice from the point of view of quantum mechanics. This can enable us to provide the first reliable estimate of how resistant to radiation damage different materials are. This property has to be well determined in order to estimate, among other things, the lifetime of critical components in future fusion reactors and in current fission reactors and in order to understand degradation mechanisms in detectors used in particle accelerators. The primary damage assessments that are available in the literature are all based on semi-empirical interaction models which are of questionable validity for the short range repulsive interactions that play an important role in the primary damage events. Therefore, an ab initio evaluation can more realistically simulate the process. The quantity of technological interest is the average threshold displacement energy. It is defined as the space angle integrated average of the minimum angular dependent threshold values. In order to validate the results, there are experimental data on certain high symmetry directions for most relevant materials. A first study of the primary damage in iron has been recently finished (PRL, submitted). For fusion it is imperative to have a reliable estimate of the threshold displacement energies in tungsten, which acts as the divertor in the fusion reactor and is thus bombarded with extreme fluxes of high energy particles. Determining the threshold displacement energy in W will be the first application in this project.