EPJ Web of Conferences (Jan 2019)

ECE Diagnostic for the initial Operation of Wendelstein 7-X

  • Hirsch Matthias,
  • Höfel Udo,
  • Oosterbeek Johan Willem,
  • Chaudhary Neha,
  • Geiger Joachim,
  • Hartfuss Hans-Jürgen,
  • Kasparek Walter,
  • Marushchenko Nikolai,
  • van Milligen Boudewijn,
  • Plaum Burkhard,
  • Stange Torsten,
  • Svensson Jakob,
  • Tsuchiya Hayato,
  • Wagner Dietmar,
  • McWeir Gavin,
  • Wolf Robert,

DOI
https://doi.org/10.1051/epjconf/201920303007
Journal volume & issue
Vol. 203
p. 03007

Abstract

Read online

The ECE diagnostic at W7-X in its standard mode of operation measures in X2 mode polarization with a 32 channel radiometer in the frequency band around 140 GHz for central magnetic field 2.5T. The radiometer is calibrated by a noise source and the overall system absolutely calibrated by means of a hot-cold source placed outside the torus in front of a Gaussian telescope optics with identical geometry and transmission line as it is installed for the measurements in the plasma vessel. The system is supplemented with a 16 channel zoom device with 4 GHz span for higher frequency resolution at a suitable radial range and a Michelson interferometer for the characterization of higher harmonics sharing the same line of sight.