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S. Stroteich

Publications and source records attributed to S. Stroteich.

2 recordsLinked to original sources

Enhanced performance in quasi-isodynamic max-$J$ stellarators with a turbulent particle pinch

Recent stellarator reactor designs demonstrate mostly outward turbulent particle transport, which, without advanced fueling technology, inhibits the formation of density gradients needed for confinement. We introduce ``SQuID-$\tau$'', a self-fueling quasi-isodynamic stellarator capable of sustaining density peaking through inward particle transport caused by turbulence. Temperature and density profile predictions based on high-fidelity gyrokinetic simulations demonstrate enhanced performance, significantly relaxing constraints on the size and magnetic field strength for reactor designs.

physics.plasm-ph

Critical gradient optimization for quasi-isodynamic stellarators

We present new and updated methods for reducing transport caused by electrostatic ion temperature gradient (ITG) driven turbulence in quasi-isodynamic (QI) configurations. We first show an updated model for the threshold (critical) gradient of localized toroidal ITG modes. It is then argued that it is desirable for ITG modes to "split" and localize in separate curvature drift wells, which is leveraged to produce a six-field-period QI configuration with a high critical gradient. We show that the destabilizing effect of kinetic electrons (Costello & Plunk 2025a) on localized ITG modes can be minimized in a magnetic field structure, which we dub "inverse mirror". Applying a general optimization target that improves ITG stability above the critical gradient yields an inverse mirror configuration, which produces heat fluxes below or equal to the W7-X high mirror configuration for a range of applied density gradients.

physics.plasm-ph