Turbulence suppression by energetic particle effects in modern optimized stellarators

Abstract

Turbulent transport is known to limit the plasma confinement of present-day optimized stellarators. To address this issue, a novel method to strongly suppress turbulence in such devices is proposed, namely the resonant wave-particle interaction of supra-thermal particles - e.g., from ion-cyclotron-resonance-frequency (ICRF) heating - with turbulence-driving microinstabilities like ion-temperature-gradient (ITG) modes. The effectiveness of this mechanism is demonstrated via analytic theory and large-scale gyrokinetic simulations, revealing an overall turbulence reduction by up to $80\%$. These results hold the promise of new and still unexplored stellarator scenarios with enhanced confinement and improved performance, essential for achieving burning plasmas in future devices.

References in corpus (2)

• Electromagnetic turbulence suppression by energetic particle driven modes
• Free energy cascade in gyrokinetic turbulence

Cited by in corpus (9)

• New high-confinement regime with fast ions in the core of fusion plasmas
• First-principles based plasma profile predictions for optimized stellarators
• Physics design point of high-field stellarator reactors
• Data-driven low-fidelity models for multi-fidelity Monte Carlo sampling in plasma micro-turbulence analysis
• Core transport barriers induced by fast ions in global gyrokinetic GENE simulations
• Predictions of improved confinement in SPARC via energetic particle turbulence stabilization
• Turbulence suppression by energetic particles: A sensitivity-driven dimension-adaptive sparse grid framework for discharge optimization
• H-mode transition in the TJ-II stellarator plasmas
• Firewall effect on electron acceleration by R-waves and parallel electric fields