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Title: Absolute calibration of sniffer probes on Wendelstein 7-X

Abstract

Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m{sup 2} per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m{sup 2} per MW injected beam power is measured.

Authors:
; ; ; ; ;  [1];  [1];  [2];  [3]
  1. Max-Planck-Institut für Plasmaphysik, Greifswald (Germany)
  2. (Germany)
  3. Eindhoven University of Technology, Eindhoven (Netherlands)
Publication Date:
OSTI Identifier:
22597680
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 8; Other Information: (c) 2016 EURATOM; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BEAMS; CALIBRATION; CONTAINERS; PROBES; QUALITY FACTOR; STRAY RADIATION

Citation Formats

Moseev, D., E-mail: dmitry.moseev@ipp.mpg.de, Laqua, H. P., Marsen, S., Stange, T., Braune, H., Erckmann, V., Gellert, F., Ernst-Moritz-Arndt-Universität Greifswald, Greifswald, and Oosterbeek, J. W.. Absolute calibration of sniffer probes on Wendelstein 7-X. United States: N. p., 2016. Web. doi:10.1063/1.4960349.
Moseev, D., E-mail: dmitry.moseev@ipp.mpg.de, Laqua, H. P., Marsen, S., Stange, T., Braune, H., Erckmann, V., Gellert, F., Ernst-Moritz-Arndt-Universität Greifswald, Greifswald, & Oosterbeek, J. W.. Absolute calibration of sniffer probes on Wendelstein 7-X. United States. doi:10.1063/1.4960349.
Moseev, D., E-mail: dmitry.moseev@ipp.mpg.de, Laqua, H. P., Marsen, S., Stange, T., Braune, H., Erckmann, V., Gellert, F., Ernst-Moritz-Arndt-Universität Greifswald, Greifswald, and Oosterbeek, J. W.. 2016. "Absolute calibration of sniffer probes on Wendelstein 7-X". United States. doi:10.1063/1.4960349.
@article{osti_22597680,
title = {Absolute calibration of sniffer probes on Wendelstein 7-X},
author = {Moseev, D., E-mail: dmitry.moseev@ipp.mpg.de and Laqua, H. P. and Marsen, S. and Stange, T. and Braune, H. and Erckmann, V. and Gellert, F. and Ernst-Moritz-Arndt-Universität Greifswald, Greifswald and Oosterbeek, J. W.},
abstractNote = {Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m{sup 2} per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m{sup 2} per MW injected beam power is measured.},
doi = {10.1063/1.4960349},
journal = {Review of Scientific Instruments},
number = 8,
volume = 87,
place = {United States},
year = 2016,
month = 8
}
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