Equilibrium reconstruction at JET using Stokes model for polarimetry

Blaise Faugeras (1) , Francesco Orsitto (1)

1 CASTOR - Control, Analysis and Simulations for TOkamak Research

This paper presents the first application to real JET data of the new equilibrium code NICE which enables the consistent resolution of the inverse equilibrium reconstruction problem in the framework of non-linear free-boundary equilibrium coupled to the Stokes model equation for polarimetry. The conducted numerical experiments enable first of all to validate NICE by comparing it to the well-established EFIT code on 4 selected high performance shots. Secondly the results indicate that the fit to polarimetry measurements clearly benefits from the use of Stokes vector measurements compared to the classical case of Faraday measurements, and that the reconstructed profiles are better constrained with smaller error bars and are closer from the profiles reconstructed by EFTM, the EFIT JET code using internal MSE constraints.

Ce travail présente la première utilisation de données réelles du tokamak JET avec le code NICE pour la reconstruction de l'équilibre d'un plasma à frontière libre et utilisant le modèle de Stokes pour la polarimétrie.

Mots clés: Tokamak equilibrium reconstruction; Stokes model polarimetry; inverse problem; PDE-constrained optimization; JET

Mots clés: Reconstruction d'équilibre; tokamak; polarimètrie; modèle de Stokes; problème inverse; EDP; optimisation

Domaines: Modélisation et simulation

Blaise Faugeras, Francesco Orsitto. Equilibrium reconstruction at JET using Stokes model for polarimetry. [Research Report] RR-9153, INRIA Sophia Antipolis - Méditerranée. 2018, pp.1-32. ⟨hal-01708553⟩