Science Working Groups

Science Working Groups (2021-2022)  - Join email lists and access files HERE

1. Core-Pedestal Confinement and Transport (Objective 1) - W. Guttenfelder

1. Transport & pedestal structure: W. Guttenfelder

   1. R(22-1):  Pedestal structure prediction based on non-ideal MHD and gyrokinetics

   2. Effect of low collisionality

   3. Effect of wall conditioning

2. Heating and Current Drive: M. Podesta

   1. R(22-2): NBI+RF synergy projections to NSTX-U and impact of modified fast ion distribution function on AE stability

   2. NBI Characterization

   3. Validate NB deposition current drive models

   4. HHFW coupling physics: SOL loss physics

2. Steady state physics (Objective 2) - R. Raman

   1. Macrostability: Demonstrate high-β, low-li discharges at low disruptivity: J. Berkery

      1. Characterization of error fields/locked modes, develop EF mitigation

      2. Mitigation of internal MHD (TMs, NTMs)

      3. Kinetic stabilization of RWM at low collisionality: real-time control

      4. Develop real-time disruption prediction and avoidance

2. Scenarios and Real-time control: Establish and optimize high non-inductive fraction operation; Particle control and heat flux mitigation necessary for stationary discharges: K. Thome

   1. Start-up/Ramp-up scenarios

   2. High non-inductive, high-performance scenarios

   3. Real-time control at high shaping

3. Boundary & exhaust physics (Objective 3) - Vlad Soukhanovskii

   1. Power exhaust: Assess performance and lifetime of new NSTX-U PFCs, and establish the physics and engineering basis to enable future PFC/divertor upgrade; Develop and evaluate power exhaust techniques for mitigating high projected NSTX-U heat fluxes - K. Gan (UTenn-Knoxville)

      1. R(22-3): Advance liquid metal PFC concept designs for NSTX-U

      2. Power exhaust and control: 

         1. Characteristics of new tiles

         2. Model validation (HEAT)

         3. SF divertors, target incidence w/r-t f/b control

         4. Attractive radiative core/divertor scenarios

         5. Impact of 3D perturbations

      3. SOL heat flux width

2. Particle control and PMI: Investigate the sustainability of particle exhaust and PMI control via lithium pumping for density and impurity control consistent with integrated scenarios - E. Unterberg (ORNL) 

   1. Particle control - develop and understand (Overlap with 2.b.III)

      1. Effect of wall conditioning

      2. Effect of fueling

      3. ELM-free, small-ELM candidates

      4. Real-time control

3. ELM stability and control: Develop and understand techniques to mitigate/eliminate edge transients and the associated enhancement of PMI - A. Kleiner

   1. ELM-free and mitigated regimes

Black: Research directed towards experimental operations

Red: Research Milestone work