Physics Designs for a Lithium Vapor Box Test at PPPL and a Lithium Vapor Detachment Experiment at Magnum-PSI*

The lithium vapor box [1] is under study as a candidate divertor. Prior to implementation in a tokamak, the concept should be tested with lab-scale experiments and in linear plasma devices. Key physics issues to be evaluated include the efflux of Li vapor (1a) without and (1b) with plasma, (2) the required density of vapor to induce detachment and volumetric recombination, (3) power spreading away from the target during volumetric recombination, (4) transport of Li ions in the plasma, and (5) pumping of H (and potentially He) emitted by a detaching plasma, using co-deposition onto liquid Li surfaces. An experiment at PPPL to test (1a) is being constructed, and the physics design for an experiment at the linear plasma device Magnum-PSI is being developed with the primary goals of measuring (1b), (2), (3), and potentially (4). We will present the physics designs of these experiments, including both practical aspects [see also Butler et al, this conference] as well as a simplified plasma model that can be adjusted to study the implications of a range of assumptions.

[1] Goldston, R.J., et al, Nucl. Mat. and Energy 12 (2017): 1118–21. https://doi.org/10.1016/j.nme.2017.03.020.