English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Understanding the behaviour of the confined fast ions is important in bothcurrent and future fusion experiments. These ions play a key role in heatingthe plasma and will be crucial for achieving conditions for burning plasma innext-step fusion devices. Microwave-based Collective Thomson Scattering (CTS)is well suited for reactor conditions and offers such an opportunity byproviding measurements of the confined fast-ion distribution function resolvedin space, time and 1D velocity space. We currently operate a CTS system atASDEX Upgrade using a gyrotron which generates probing radiation at 105 GHz. Anew setup using two independent receiver systems has enabled improvedsubtraction of the background signal, and hence the first accuratecharacterization of fast-ion properties. Here we review this new dual-receiverCTS setup and present results on fast-ion measurements based on the improvedbackground characterization. These results have been obtained both with andwithout NBI heating, and with the measurement volume located close to thecentre of the plasma. The measurements agree quantitatively with predictions ofnumerical simulations. Hence, CTS studies of fast-ion dynamics at ASDEX Upgradeare now feasible. The new background subtraction technique could be importantfor the design of CTS systems in other fusion experiments.

Improved Collective Thomson Scattering measurements of fast ions at ASDEX Upgrade