First results from the implementation of the ITER diagnostic residual gas analyzer prototype at Wendelstein 7-X

G Schlisio; C C Klepper; J H Harris; T M Biewer; V R Winters; U Wenzel; P Kornejew; H Laqua; M Krychowiak; W7-X team

doi:10.1063/1.5098125

First results from the implementation of the ITER diagnostic residual gas analyzer prototype at Wendelstein 7-X

Rev Sci Instrum. 2019 Sep;90(9):093501. doi: 10.1063/1.5098125.

Authors

G Schlisio¹, C C Klepper², J H Harris², T M Biewer², V R Winters³, U Wenzel¹, P Kornejew¹, H Laqua¹, M Krychowiak¹; W7-X team⁴

Affiliations

¹ Max-Planck-Institut für Plasmaphysik, Wendelsteinstraße 1, 17491 Greifswald, Germany.
² Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169, USA.
³ University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
⁴ Max-Planck-Institut für Plasmaphysik, Wendelsteinstraße 1, 17491 Greifswald, GermanyOak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169, USAUniversity of Wisconsin-Madison, Madison, Wisconsin 53706, USA.

PMID: 31575247
DOI: 10.1063/1.5098125

Abstract

Fusion reactors and long pulse fusion experiments heavily depend on a continuous fuel cycle, which requires detailed monitoring of exhaust gases. We have used a diagnostic residual gas analyzer (DRGA) built as a prototype for ITER and integrated it on the most advanced stellarator fusion experiment, Wendelstein 7-X (W7-X). The DRGA was equipped with a sampling tube and assessed for gas time of flight sample response, effects of magnetic field on gas detection and practical aspects of use in a state of the art fusion environment. The setup was successfully commissioned and operated and was used to observe the gas composition of W7-X exhaust gases. The measured time of flight gas response was found to be in the order of a second for a 7 m sample tube. High values of magnetic field were found to affect the partial pressure readings of the DRGA and suggest that additional shielding is necessary in future experimental campaigns.