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arXiv · 2507.12287

Gauss' Separation Algorithm for the Magnetic Field Decomposition of the SPARC PRD simulation

Gregorio L Trevisan·Ryan M Sweeney·Robert S Granetz
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Abstract

A magnetic separation algorithm originally introduced by Gauss has been revisited in recent years with application to magnetically-confined fusion experiments. The main result offered by Gauss' Separation Algorithm~(GSA) is a magnetic field computation that enables the decomposition of the contributions due to sources internal and external to a bounded volume through the generalized Virtual-Casing Principle. The present work applies GSA to simulations of the SPARC Primary Reference Discharge and demonstrates its separation capability on all phases of the shot, including the ramp-up during which significant currents on the passive structures often complicate the reconstruction of plasma equilibria. Such early results suggest a promising new way to study ramp-ups, disruptions, and vertical displacement events without any specific modeling assumption. Envisaged applications include reading magnetic data from experimental diagnostics and producing a new set of signals without external contributions to be used by downstream equilibrium codes for improved accuracy or speed.

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Gregorio L Trevisan, Ryan M Sweeney, Robert S Granetz. 2025-07-16. Gauss' Separation Algorithm for the Magnetic Field Decomposition of the SPARC PRD simulation. https://arxiv.org/abs/2507.12287

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