This work addresses the question of the relation between strike-point
splitting and magnetic stochasticity at the edge of a poloidally diverted
tokamak in the presence of externally imposed magnetic perturbations. More
specifically, ad-hoc helical current sheets are introduced in order to mimic a
hypothetical screening of the external resonant magnetic perturbations by the
plasma. These current sheets, which suppress magnetic islands, are found to
reduce the amount of splitting expected at the target, which suggests that
screening effects should be observable experimentally. Multiple screening
current sheets reinforce each other, i.e. less current relative to the case of
only one current sheet is required to screen the perturbation.Comment: Accepted in the Proceedings of the 19th International Conference on
Plasma Surface Interactions, to be published in Journal of Nuclear Materials.
Version 2: minor formatting and text improvements, more results mentioned in
the conclusion and abstrac
