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arXiv · 2504.05775

Survey of the Edge Radial Electric Field in L-mode TCV Plasmas using Doppler Backscattering

Sascha Rienäcker·Pascale Hennequin·Laure Vermare·Cyrille Honoré·Stefano Coda·Benoit Labit·Benjamin Vincent·Yinghan Wang·Lorenzo Frassinetti·Olivier Panico
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Abstract

A Doppler backscattering (DBS) diagnostic has recently been installed on the Tokamak \`a Configuration Variable (TCV) to facilitate the study of edge turbulence and flow shear in a versatile experimental environment. The dual channel V-band DBS system is coupled to TCV's quasi-optical diagnostic launcher, providing access to the upper low-field side region of the plasma cross-section. Verifications of the DBS measurements are presented. The DBS equilibrium $v_\perp$ profiles are found to compare favorably with gas puff imaging (GPI) measurements and to the $E_r$ inferred from the radial force balance of the carbon impurity. The radial structure of the edge $E_r \times B$ equilibrium flow and its dependencies are investigated across a representative set of L-mode TCV discharges, by varying density, auxiliary heating and magnetic configuration.

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Sascha Rienäcker, Pascale Hennequin, Laure Vermare, Cyrille Honoré, Stefano Coda, Benoit Labit, Benjamin Vincent, Yinghan Wang, Lorenzo Frassinetti, Olivier Panico. 2025-04-08. Survey of the Edge Radial Electric Field in L-mode TCV Plasmas using Doppler Backscattering. https://doi.org/10.1088/1361-6587%2Fadd0e0

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