Diagnostics design for steady-state operation of the Wendelstein 7-X stellarator

Abstract

Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):König, R., Baldzuhn, J., Biel, W. . W., Biedermann, C., Burhenn, R., Bozhenkov, S., ... Zoletnik, S. (2010). Diagnostics design for steady-state operation of the Wendelstein 7-X stellarator. Review of Scientific Instruments, 81(10), 10E133-1/5. [10E133]. DOI: 10.1063/1.3483210 General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. The status of the diagnostic developments for the quasistationary operable stellarator Wendelstein 7-X ͑maximum pulse length of 30 min at 10 MW ECRH heating at 140 GHz͒ will be reported on. Significant emphasis is being given to the issue of ECRH stray radiation shielding of in-vessel diagnostic components, which will be critical at high density operation requiring O2 and OXB heating.

Charge exchange recombination spectroscopy at Wendelstein 7-X

“…At the planned peak performance of W7-X, heat loads of up to 100kW m −2 are expected on the plasma facing components from plasma radiation and ECRH stray radiation. Combined with the planned long pulse operation of up to 30 minutes, this places extreme design requirements on W7-X diagnostics, which are covered in detail elsewhere 19 . However, since the CXRS system requires the NBI, which is only available for periods of up to 10s every few minutes, the sensitive components can be covered for longer periods, significantly reducing the design requirements on them.…”

Aspects of steady-state operation of the Wendelstein 7-X stellarator

“…A comprehensive overview is given in Hartfuss et al 2006. The requirements range from steady state detection and data acquisition to protection against even low radiation and particle fluxes from the plasma, often requiring elaborate cooling techniques (König et al 2010). In addition, a steady state plasma experiment asks for diagnostics which are capable to continuously monitor the plasma facing components.…”

Towards a new image processing system at Wendelstein 7-X: From spatial calibration to characterization of thermal events

“…5 mm/pixel. [5][6][7][8] The MWIR system consisted of a high-resolution IR camera, measuring at 3-5 µm, 125 Hz full-frame rate, 1344 × 768 pixels, viewing the central tiles of the limiter in module 3 with a spatial resolution of ca. 1 mm/pixel.…”