Optimization of the Collective Thomson scattering diagnostic for future operation

W7-X Team, I. Abramovic*, D. Moseev, T. Stange, S. Marsen, W. Kasparek, S.K. Nielsen, A. Tancetti, M. Salewski, A. Pavone, J. P. Svensson, R.C. Wolf, H.P. Laqua, N.J. Lopes Cardozo

*Corresponding author for this work

Research output: Contribution to journalConference articleResearchpeer-review

Abstract

Collective Thomson scattering (CTS) is a microwave diagnostic allowing measurements of a number of plasma parameters such as the bulk ion temperature, the plasma composition, drift velocities and fast ion velocity distribution function. A CTS system has been successfully installed and commissioned on the Wendelstein 7-X (W7-X) stellarator. The measured spectra are analyzed by the means of the CTS forward model eCTS and the Minerva scientific framework enabling the use of Bayesian inference of relevant plasma parameters. Here we discuss the options for further optimization of the CTS diagnostic and focus on two topics of importance for the inference of bulk ion temperature values from CTS spectra: influence of impurities on the CTS spectra and the width of the notch filters that are employed to protect the receiver from high-power radiation. In addition to that we discuss the possibility of effective charge measurements by CTS. We explore the existence of an optimal notch filter width.
Original languageEnglish
Article numberC10021
JournalJournal of Instrumentation
Volume14
Issue number10
Number of pages7
ISSN1748-0221
DOIs
Publication statusPublished - 2019
Event3rd European Conference on Plasma Diagnostics - Lisbon, Portugal
Duration: 6 May 201910 May 2019

Conference

Conference3rd European Conference on Plasma Diagnostics
CountryPortugal
CityLisbon
Period06/05/201910/05/2019

Keywords

  • Nuclear instruments and methods for hot plasma diagnostics
  • Analysis and statistical methods

Cite this

W7-X Team, Abramovic, I., Moseev, D., Stange, T., Marsen, S., Kasparek, W., ... Cardozo, N. J. L. (2019). Optimization of the Collective Thomson scattering diagnostic for future operation. Journal of Instrumentation, 14(10), [C10021]. https://doi.org/10.1088/1748-0221/14/10/C10021