Hyperion Center Stack
The center stack is the slender central column that carries the toroidal-field return, the solenoid, and the inboard shielding.
The defining component
In a spherical tokamak the center stack is the single most demanding structure. It is the narrow column running up the machine axis that packs together the inboard toroidal-field conductor, the central solenoid, inboard shielding, and their cooling, all in the smallest radius the physics will allow. The tighter this column, the more spherical the plasma and the better the confinement, so every millimeter is contested.
What it carries
- The inboard legs of the toroidal-field system, which set the 8 T on-axis field.
- The central solenoid used to induce and drive plasma current.
- Inboard neutron shielding protecting the conductors.
- Coolant paths that remove nuclear and resistive heating.
The REBCO advantage
Hyperion uses high-temperature REBCO superconductor in the center stack. REBCO carries very high current density at high field, which lets the central column be both slender and capable of the 16.84 T peak field the design requires. This is the enabling technology for a compact spherical tokamak; a conventional conductor could not fit the same performance into the same radius.
In the model
Selecting the center stack isolates the column and, for signed-in users, breaks it into its concentric layers. The exploded view lifts the stack along the machine axis, which shows how it is intended to be assembled and, eventually, maintained as a unit.
Why it is stressed
The center stack sees the highest field, high neutron flux, and large structural loads at once. Its design is a central subject of the Hyperion engineering work. Continue to the toroidal-field coils and the central solenoid it houses.