Stellarator, heliotron and torsatron
Devices whose rotational transform is produced by external non-axisymmetric coil systems rather than by a driven plasma current. SCPN-STELLARATOR-CORE owns the device truth of the stellarator, heliotron and torsatron configurations.
What the configuration is
A stellarator twists its field lines with the coils alone: helical or modular three-dimensional windings produce the rotational transform that a tokamak gets from its plasma current. There is therefore no net current to drive and no current-driven disruption to avoid, at the price of a three-dimensional geometry that must be optimised for confinement. Heliotrons and torsatrons are the continuous-helical-coil branches of the same family; quasi-symmetry classes and island divertor layouts are configuration facets, not separate claims.
What the core owns
- the device boundary: plant and experiment truth, discharge lifecycle and configuration policy for stellarators, heliotrons and torsatrons;
- the declared configuration: major radius, average minor radius, number of field periods, rotational transform; coil realisation kind, coil count and auxiliary coil count; field on axis, volume-averaged beta and flat-top duration as operational limits;
- diagnostic semantics, three-dimensional reference frames and clock identity declarations; actuator-response model boundaries and the declared safety envelope; the device-owned CONTROL adapter specification;
- the binding to the SCPN Phase Orchestrator reactor registry (version 1.0.0) and the machine-readable domain manifest.
What it explicitly excludes
- Axisymmetric tokamaks: SCPN-TOKAMAK-CORE; reversed-field pinch: SCPN-RFP-CORE; spheromak: SCPN-SPHEROMAK-CORE; FRC: SCPN-FRC-CORE.
- Three-dimensional equilibrium and stellarator solver work, explicitly: SCPN-Fusion-Core.
- Typed signal semantics and comparability: SCPN-Phase-Orchestrator (review-only output, never actuation).
- Control admission and action formation: SCPN-Control is the sole software authority that forms an admitted control action.
- Machine protection: independent systems retain the final veto. Portfolio presentation, identity, entitlement and execution gating: SCPN-Studio.
Level-0 physics and its anchor
No level-0 physics is implemented in this core yet. The stellarator core has two implemented capabilities, the device configuration model and the diagnostic and clock semantics model; it evaluates no closed form, and the explorer of this family has no stellarator tab for that reason. The three-dimensional equilibrium that defines a stellarator is solver work that belongs to SCPN-Fusion-Core until an exact surface passes the family migration gate. What the core does carry is the declared parameter set above, validated with documented consistency estimates and serialised canonically with a SHA-256 digest.
Non-claims
- No equilibrium, stability, transport or coil-optimisation calculation exists in the repository.
- No parameter set describes or validates any real machine; no channel describes a real diagnostic.
- The repository is not machine-ready, not safety-certified and not reactor-ready.
Capabilities and evidence
Evidence maturity computational_prototype, two implemented capabilities, each with its evidence record in VALIDATION.md: the device configuration model (validated parameter objects with documented consistency estimates, canonical serialisation, a data-only SPO registry pin) and the diagnostic and clock semantics model (synthetic channel and clock declarations aligned fail-closed with the pinned SPO observability catalogue, three-dimensional reference frames). No parameter set or channel describes any real machine or diagnostic; the claim inventory is empty and verified by the domain validator.