Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)

M. Krychowiak*, A. Adnan, A. Alonso, T. Andreeva, J. Baldzuhn, T. Barbui, M. Beurskens, W. Biel, C. Biedermann, B. D. Blackwell, H. S. Bosch, S. Bozhenkov, R. Brakel, T. Bräuer, B. Brotas De Carvalho, R. Burhenn, B. Buttenschön, A. Cappa, G. Cseh, A. CzarneckaA. Dinklage, P. Drews, A. Dzikowicka, F. Effenberg, M. Endler, V. Erckmann, T. Estrada, O. Ford, T. Fornal, H. Frerichs, G. Fuchert, J. Geiger, O. Grulke, J. H. Harris, H. J. Hartfuß, D. Hartmann, D. Hathiramani, M. Hirsch, U. Höfel, S. Jabłoński, M. W. Jakubowski, J. Kaczmarczyk, T. Klinger, S. Klose, J. Knauer, G. Kocsis, R. König, P. Kornejew, A. Krämer-Flecken, N. Krawczyk, T. Kremeyer, I. Ksiazek, M. Kubkowska, A. Langenberg, H. P. Laqua, M. Laux, S. Lazerson, Y. Liang, S. C. Liu, A. Lorenz, A. O. Marchuk, S. Marsen, V. Moncada, D. Naujoks, H. Neilson, O. Neubauer, U. Neuner, H. Niemann, J. W. Oosterbeek, M. Otte, N. Pablant, E. Pasch, T. Sunn Pedersen, F. Pisano, K. Rahbarnia, L. Ryć, O. Schmitz, S. Schmuck, W. Schneider, T. Schröder, H. Schuhmacher, B. Schweer, B. Standley, T. Stange, L. Stephey, J. Svensson, T. Szabolics, T. Szepesi, H. Thomsen, J. M. Travere, H. Trimino Mora, H. Tsuchiya, G. M. Weir, U. Wenzel, A. Werner, B. Wiegel, T. Windisch, R. Wolf, G. A. Wurden, D. Zhang, A. Zimbal, S. Zoletnik

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    51 Citations (Scopus)

    Abstract

    Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.

    Original languageEnglish
    Article number11D304
    JournalReview of Scientific Instruments
    Volume87
    Issue number11
    DOIs
    Publication statusPublished - 1 Nov 2016

    Fingerprint

    Dive into the research topics of 'Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)'. Together they form a unique fingerprint.

    Cite this