Erlangen 2018 – wissenschaftliches Programm
P 19.4: Poster
Mittwoch, 7. März 2018, 16:15–18:15, Zelt Ost
Estimation, Validation and Uncertainty of the Position of the Separatrix Contour at ASDEX Upgrade — •Johannes Illerhaus1,2, Rainer Fischer1, Gregor Birkenmeier1,2, Mike Dunne1, Louis Giannone1, Bernd Kurzan1, Patrick McCarthy1, Matthias Willensdorfer1, Ulrich Stroth1,2, and the ASDEX Upgrade Team1 — 1Max Planck Institute for Plasma Physics, Garching, Germany — 2Physics Department E28, TUM, Garching, Germany
To properly describe magnetic equilibria of tokamak plasmas in fusion research it is important to be able to accurately reconstruct the posi- tion of the last closed flux surface, the separatrix. Measurements of the currents of the scrape-off-layer onto the divertor plates, in the poloidal field coils and those induced in vessel components are used to apply constraints to this reconstruction. The influence of the uncertainties in these quantities on the separatrix reconstruction will be studied. In this contribution the goal is to illustrate the uncertainty and sensitivity of the reconstructed separatrix position and their respective dependence on the allowed flexibilities in the prescribed coil currents. Different ki- netic diagnostics (Thomson scattering,electron cyclotron emission and lithium beam) are used to validate the reconstructed separatrix po- sition. Additionally, different poloidal field coil arrays can be used to better understand their influence on the equilibrium reconstruction. The result will be an uncertainty quantification of the separatrix con- tour and a study of the systematic deviations of the diagnostics among themselves and with respect to the equilibrium, respectively.