1. Plasma Wall Interaction Panel-Potential Thrusts
Modest effort: 10 M$ (~ 2 M$/yr for 5 yrs; w/follow-on)
Modest enhanced effort in plasma/material interaction predictive modeling & code validation.
Moderate effort: 40 M$ (~ 8 M$/yr for 5 yrs: w/follow-on)
More ambitious plasma/material interaction modeling increase + major diagnostic increase + modest facility use/upgrades + innovative solution research
High effort: 50 M$  (5+ yrs)
Major increase in plasma/material interaction modeling, diagnostics, innovative solution research, + major facility construction/upgrades.

2. Additional PWI Thrust Minimal cost/high leverage: 1 M$, 1 year
Fund purchase of 20 diagnostics
To diagnose SOL/edge plasma, near-surface plasma, sheath, and material surface time-evolution
(Install/use diagnostics via base program funding)

3. Plasma Wall Interaction Panel-typical Modest Thrust
GOAL: Some increase in our predictive PWI modeling capability; help identify workable surface materials, PFC designs, plasma operating parameters.
Modest effort: 10 M$ (~ 2 M$/yr for 5 yrs; ~5 FTE’s/yr increase) w/follow-on after the initial 5 yr work.
Modest enhanced effort in plasma/material interaction predictive modeling & code validation.
Areas: Edge/SOL plasma with turbulence, sputtering erosion/redeposition, transient plasma effects on PFC,s, dust effects, RF sheath effects. Analysis of present devices, ITER, start of PWI DEMO analysis. Code/data validation efforts.
We are on a steep portion of the “learning curve”. Thrust 1 would permit highly cost-effective enhancement to the existing highly-underfunded modeling/computation capability, but still leaving major gaps.
Potentially includes small increases in experimental capability, e.g., addition of low-cost diagnostics.
This (and all PWI research thrusts) would interact with thrusts/efforts to increase operating time, new device construction, supercomputer applications (e.g., Fusion Simulation Project), transient plasma control, core plasma theory/modeling, and similar relevant areas.

4. Plasma Wall Interaction Panel-potential Moderate Thrust
GOAL: Significant Increase in our predictive PWI modeling capability; help identify workable materials, PFC designs, plasma operating parameters.
Moderate effort: 40 M$ (~ 8 M$/yr for 5 yrs; ~15 FTE’s) w/follow-on
Significant plasma/material interaction modeling increase + diagnostic increase + moderate increased facility use/upgrades + innovative solution research.
Areas: Includes 3-D time-dependent turbulence modeling, coupled (edge plasma/material surface/impurity transport) erosion/redeposition analysis, comprehensive transient analysis, dust, microstructural surface response, etc.
Analysis of US devices (CMOD, NSTX, DIII-D,) JET, and selected other tokamaks, plasma simulators (PISCES, plasma guns, etc.), DEMO.
includes moderate increases in experimental capability, e.g., addition of key diagnostics, increased operating time, but does not include major facility construction or major upgrades

5. Plasma Wall Interaction Panel- potential High Thrust
GOAL: Major increase in our predictive PWI modeling cabability; Identify workable materials, PFC designs, plasma operating parameters.
High effort: 50 M$  (5+ yrs) 15+ FTE’s/yr increase (note: staff availability is a rate-limiting step).
Includes Thrust-2 modeling goals
Major increases in experimental capability, including diagnostics, operating time, new test facilities (e.g., lab simulator + tokamak).