| Autor: |
Nelson AO; Columbia University, New York, New York 10027, USA., Schmitz L; University of California-Los Angeles, Los Angeles, California 90095, USA., Paz-Soldan C; Columbia University, New York, New York 10027, USA., Thome KE; General Atomics, San Diego, California 92186, USA., Cote TB; General Atomics, San Diego, California 92186, USA., Leuthold N; Columbia University, New York, New York 10027, USA., Scotti F; Lawrence Livermore National Laboratory, Livermore, California 94550, USA., Austin ME; The University of Texas at Austin, Austin, Texas 78712, USA., Hyatt A; General Atomics, San Diego, California 92186, USA., Osborne T; General Atomics, San Diego, California 92186, USA. |
| Abstrakt: |
In a series of high performance diverted discharges on DIII-D, we demonstrate that strong negative triangularity (NT) shaping robustly suppresses all edge-localized mode (ELM) activity over a wide range of plasma conditions: ⟨n⟩=0.1-1.5×10^{20} m^{-3}, P_{aux}=0-15 MW, and |B_{t}|=1-2.2 T, corresponding to P_{loss}/P_{LH08}∼8. The full dataset is consistent with the theoretical prediction that magnetic shear in the NT edge inhibits access to ELMing H-mode regimes; all experimental pressure profiles are found to be at or below the infinite-n ballooning stability limit. Our present dataset also features edge pressure gradients in strong NT that are closer to an H-mode than a typical L-mode plasma, supporting the consideration of NT for reactor design. |
