SPECTRAX-GK

SPECTRAX-GK is a JAX-native gyrokinetic solver using Hermite-Laguerre velocity space, Fourier perpendicular coordinates, and field-aligned flux-tube geometry.

Install with pip install spectraxgk and run spectraxgk in a terminal to launch the default linear Cyclone demo. The same executable also accepts checked-in TOMLs directly and can plot saved runtime outputs with spectraxgk --plot <artifact>.

Documentation map

The documentation is organized so that the core physics, equations, numerical methods, and model-specific paths are easy to locate:

Theory summarizes the gyrokinetic ordering, field equations, and flux-tube assumptions.
Linear Model And Derivations gives the operator-level derivation tied directly to the implemented linear equations and diagnostics.
Operators And Terms lists every implemented term, collision model, hyperdiffusion/hypercollision control, and the runtime parameters that select them.
Numerics documents discretization, time integration, FFT brackets, solver contracts, and JAX parallelization.
Geometry and Input Files and Executable cover the supported model paths (analytic s-alpha, Miller, VMEC/imported geometry, slab) together with the TOML schema used by the executable and Python drivers.

For a first technical read, start with Theory, then move to Operators And Terms and Numerics. That path gives the governing equations, the term-by-term implementation contract, and the numerical approximations in the same order they appear in the code.

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