High performance advanced tokamak regimes in DIII-D for next-step experiments

Advanced Tokamak (AT) research in DIII-D was carried out to provide a scientific basis for steady-state high performance operation in future devices. The tools that were under development for controlling the regimes were described and the methods used to combine them to produce AT scenarios that project forward to steady state high performance in a burning plasma. The experiments indicate that the β limits were maximized by strong shaping and broad pressure profiles. Close coupling between modeling and experiment was found to be key to understanding the separate elements, their complex nonlinear interactions, and their integration into self-consistent high performance scenarios.