# Plasma Module Guide

The plasma module covers ideal-MHD stability, equilibrium, and figures of merit for tokamaks, stellarators, and field-reversed configurations (FRCs).

## Standard tabs

| Tab | What it computes | Anchor reference |
|---|---|---|
| Circular Tokamak | δW MHD stability vs aspect ratio | Troyon 1984 |
| Shaped Tokamak | δW with κ and δ | ITER Physics Basis 1999 |
| Negative Triangularity | reverse-D ELM-suppression scenario | Camenen 2007 |
| Stellarator | iota-based stability with well and Shafranov shift | W7-X 2019, LHD 2010 |
| FRC | tilt-mode with s\* and ρ\* | Belova 2003, TAE 2015 |
| Eigenmode | radial structure of ξ(s) displacement | Bussac 1975 |
| Simulation | β-ramp animation | — |

## Pro tabs

**Optimizer** — brute-force grid search across κ, δ, A, ι, well_depth.
**Predictor** — recommend nearest stable config from optimizer output.
**Constraints** — enforce engineering limits (q_95, n_GW, β_N).
**Export** — CSV/JSON/BibTeX bundle for publication.

## Research-grade tabs (2026-05)

**Equilibrium (Soloviev)** — closed-form Grad-Shafranov benchmark.
**Ballooning (s-α)** — Connor-Hastie-Taylor 1979 local stability.
**Mercier** — interchange criterion, decomposed into well/shear/current.
**Multi-mode δW** — (m,n) family scan with coupling matrix.
**Sensitivity** — ∂β_N/∂x · x/β_N elasticity, ranked.
**Convergence** — Richardson extrapolation across n_radial.
**EFIT Import** — g-eqdsk file parser.
**Validation Suite** — one-click verify against 8 canonical references.

## Suggested workflow

1. Run **Equilibrium** with your geometry. Confirm I_p and β_N look right.
2. Run **Validation Suite** against the experiment closest to your geometry. Match should be within tolerance.
3. Run **Ballooning** at your operating point. Find where you sit on the s-α plane.
4. Run **Multi-mode**. Identify the dominant unstable mode and its resonant surface.
5. Run **Sensitivity**. Decide which parameter to tune.
6. Run **Convergence**. Prove the result is grid-converged before quoting it.

## Primary references

- Troyon et al. 1984, [Plasma Phys. Control. Fusion 26, 209](https://doi.org/10.1088/0741-3335/26/1A/305)
- Connor, Hastie, Taylor 1979, [Proc. R. Soc. A 365, 1](https://doi.org/10.1098/rspa.1979.0010)
- Mercier 1962, Nucl. Fusion 1, 47
- Soloviev 1968, [Sov. Phys. JETP 26, 400](http://jetp.ras.ru/cgi-bin/dn/e_026_02_0400.pdf)
- Greenwald 2002, [Plasma Phys. Control. Fusion 44, R27](https://doi.org/10.1088/0741-3335/44/8/201)
- Wesson 2004, "Tokamaks" 3rd ed.
- Klinger et al. 2019 (W7-X), [Nucl. Fusion 59, 112004](https://doi.org/10.1088/1741-4326/ab03a7)
- Binderbauer et al. 2015 (TAE), [Phys. Plasmas 22, 056110](https://doi.org/10.1063/1.4920950)