Magnetic flux surface (JFIT) reconstructions of plasma motion during an unmitigated VDE.
Overview of diagnostics used in the experiment showing (a) top view, (b) IR camera view and divertor shelf probes, (c) lower divertor filterscope view chords, and (d) AXUV photodiode array view chords at toroidal angle.
Overview of VDE experiment time traces showing (a) vertical position, (b) plasma current, (c) total toroidally averaged radiated power, (d) line-integrated electron density, and (e) divertor electron temperature for a single shot (with dashed curve showing an average across the entire lower divertor).
Contour plots of heat loads to lower divertor vs. time from IR camera for (a) VDE with forward and (b) VDE with reversed . Refer to Fig. 1 for locations of the areas marked in the divertor.
(a)–(d) Total emissivity contours and (e)–(h) images of a VDE at four different time steps. Time (c) corresponds to the peak radiation ( spike) and time (d) is during the CQ. Green curves are JFIT magnetic flux contours.
Radial profiles of (a) estimated heat flux (including overlay of total line integrated plasma radiant brightness) and (b) carbon sputtering across the lower divertor at start of the CQ from various diagnostics.
Time traces during an unmitigated VDE showing (a) plasma current, (b) toroidal wall current, (c) poloidal wall current, and (d) vertical vessel displacement.
Power deposition vs. time for (a) unmitigated and (b) mitigated VDE.
Trends in heat deposition and sputtering in VDEs as a function of MGI injection delay showing (a) conducted energy to divertor shelf edge and center, (b) total radiated energy, and (d) total divertor sputtered carbon.
Trends vessel currents and forces as a function of MGI injection delay showing (a) peak toroidal wall current, (b) peak poloidal wall current, (c) toroidal peaking factor of toroidal wall current, and (d) magnitude of peak vertical vessel displacement.
Sequence of fast bolometry showing radiated power emissivity at four time steps for VDEs with (a) downward kick and forward BT, (b) downward kick and reversed BT, and (c) upward kick and reversed BT. Arrows indicate halo current ion flow direction. The drift direction is the same as shown by arrows if plasma is positively charged.
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