Magnetic diagnostics for the lithium tokamak experiment.

Area of Science:

• Plasma Physics
• Fusion Energy Research
• Materials Science

Background:

• Magnetic confinement fusion relies on minimizing plasma-wall interactions.
• Traditional tokamaks face challenges with plasma-recycling and impurity influx.
• Novel materials and configurations are needed to enhance plasma performance.

Purpose of the Study:

• Investigate the novel low-recycling lithium wall operating regime in the Lithium Tokamak Experiment (LTX).
• Assess the effectiveness of an in-vessel liquid lithium shell for plasma confinement.
• Characterize plasma behavior and equilibrium reconstructions within this unique operational regime.

Main Methods:

• Utilized the Lithium Tokamak Experiment (LTX), a spherical tokamak with specific dimensions (R(0)=0.4 m, a=0.26 m).
• Employed an in-vessel shell coated with liquid lithium, heated to achieve the low-recycling regime.
• Deployed an extensive array of magnetic diagnostics (Mirnov coils, flux loops, Rogowskii coils, diamagnetic loop) to monitor plasma behavior.

Main Results:

• Successfully operated the LTX in a novel low-recycling regime using a liquid lithium wall.
• Characterized the plasma equilibrium with high precision using a constrained reconstruction approach.
• Demonstrated the feasibility of using robust, heat- and lithium-resistant diagnostics within the experimental setup.

Conclusions:

• The liquid lithium wall in LTX facilitates a low-recycling operating regime, crucial for future fusion devices.
• Advanced magnetic diagnostics are essential for understanding and controlling plasma in such novel configurations.
• The LTX experiment provides valuable data for the development of magnetically confined fusion energy.