DIII-D: Next Steps on the Reactor Path

The DIII-D program is pursuing a mission to confront the challenges of burning plasmas in ITER and to provide a cost-effective path to reducing physics and engineering risks of a Fusion Pilot Plant. Over the next three years, planned experiments and upgrades at DIII-D target a dissipative power handling solution integrated with a high-performance fusion core. This includes the development and validation of new current drive tools for reactor regimes. An increase in plasma shaping and toroidal field will maximize plasma pressure and density, allowing high opacity/low collisionality regimes to be investigated for core-edge integration. A new modular divertor approach will enable DIII-D to explore optimum configurations for a reactor, benefiting also from a dedicated material interaction test station. Low torque heating and profile control from increased gyrotron power of 6 MW together with plasma control upgrades, will facilitate studies of burning plasma physics and performance limits. Longer term, controlling and mitigating plasma transients using improved magnetic 3D coils and passive runaway destabilizing coils are planned. A balanced approach is now adopted for the DIII-D program to deliver operational reliability, efficiency, and upgrades, thereby laying the foundation for future facility operation at “full potential” for the US fusion research program and collaborators.