Publications by authors named "A Fellman"

As the basis of radiation safety practice and regulations worldwide, the linear no-threshold (LNT) hypothesis exerts enormous influence throughout society. This includes our judicial system, where frivolous lawsuits are filed alleging radiation-induced health effects caused by negligent companies who subject unwitting victims to enormous financial and physical harm. Typically, despite the lack of any supporting scientific basis, these cases result in enormous costs to organizations, insurance companies, and consumers.

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A large and increasing number of different types of interatomic potentials exist, either based on parametrised analytical functions or machine learning. The choice of potential to be used in a molecular dynamics simulation should be based on the affordable computational cost and required accuracy. We develop and compare four interatomic potentials of different complexity for iron: a simple machine-learned embedded atom method (EAM) potential, a potential with machine-learned two- and three-body-dependent terms, a potential with machine-learned EAM and three-body terms, and a Gaussian approximation potential with the smooth overlap of atomic positions descriptor.

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We have performed a systematic molecular dynamics investigation of the effects of overlap of collision cascades in tungsten with pre-existing vacancy-type defects. In particular, we focus on the implications for fusion neutron irradiated tungsten in relation to comparisons with damage production under ion irradiation conditions. We find that overlap of a cascade with a vacancy-type defect decreases the number of new defects with roughly the same functional dependence as previously shown for interstitial clusters.

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