Recombination of open-f-shell tungsten ions

Krantz, C and Badnell, N R and Müller, A and Schippers, S and Wolf, A (2017) Recombination of open-f-shell tungsten ions. Journal of Physics B: Atomic, Molecular and Optical Physics, 50 (5). ISSN 0953-4075

[img]
Preview
Text (Krantz-etal-JOP-B-2017-Recomination-of-open-f-shell-tungsten)
Krantz_etal_JOP_B_2017_Recomination_of_open_f_shell_tungsten.pdf
Accepted Author Manuscript

Download (986kB)| Preview

    Abstract

    We review experimental and theoretical efforts aimed at a detailed understanding of the recombination of electrons with highly charged tungsten ions characterised by an open 4f sub-shell. Highly charged tungsten occurs as a plasma contaminant in ITER-like tokamak experiments, where it acts as an unwanted cooling agent. Modelling of the charge state populations in a plasma requires reliable thermal rate coefficients for charge-changing electron collisions. The electron recombination of medium-charged tungsten species with open 4f sub-shells is especially challenging to compute reliably. Storage-ring experiments have been conducted that yielded recombination rate coefficients at high energy resolution and well-understood systematics. Significant deviations compared to simplified, but prevalent, computational models have been found. A new class of ab initio numerical calculations has been developed that provides reliable predictions of the total plasma recombination rate coefficients for these ions.