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DOE OSTI · 2437698

Visible core spectroscopy at Wendelstein 7-X

Ford, O. P.·Langenberg, A.·Romba, T.·Pölöskei, P.·Zanini, M.·Bannmann, S.·Gonda, T.·Ida, K.·Lopez Cansino, R.·Pablant, N.·de la Riva Villen, J.·Swee, C.·Yoshinuma, M.·Alonso, A.·Geiger, B.·Perseo, V.·Viezzer, E.
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Abstract

This paper presents an overview of recent hardware extensions and data analysis developments to the Wendelstein 7-X visible core spectroscopy systems. These include upgrades to prepare the in-vessel components for long-pulse operation, nine additional spectrometers, a new line of sight array for passive spectroscopy, and a coherence imaging charge exchange spectroscopy diagnostic. Progress in data analysis includes ion temperatures and densities from multiple impurity species, a statistical comparison with x-ray crystal spectrometer measurements, neutral density measurements from thermal passive Balmer-alpha emission, and a Bayesian analysis of active hydrogen emission, which is able to infer electron density and main ion temperature profiles.

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Ford, O. P., Langenberg, A., Romba, T., Pölöskei, P., Zanini, M., Bannmann, S., Gonda, T., Ida, K., Lopez Cansino, R., Pablant, N., de la Riva Villen, J., Swee, C., Yoshinuma, M., Alonso, A., Geiger, B., Perseo, V., Viezzer, E.. 2024-08-13. Visible core spectroscopy at Wendelstein 7-X. https://doi.org/10.1063/5.0219469

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