Speaker
Petr Böhm
Description
The Thomson scattering (TS) diagnostic system on the COMPASS tokamak consists of separate collection optics for core and edge plasma. Till now, the adverse orientation of the viewport available for the edge TS limited the investigated plasma scenarios to those, where H-mode plasma pedestal was possible to be observed. The vacuum vessel port has been recently modified and directed more to the plasma edge. To bridge the time for designing and manufacturing a new lens, the so far used edge TS collection lens was tilted and the fibre bundles rearranged to comply with the new geometry. However, the full potential of the new port is utilized only by the newly designed and manufactured lens. Comparison of performance of the collection lenses before and after the viewport modification is presented. Apart from the edge collection system upgrade, the laser system was extended by two lasers with parameters similar to the original two, thus increasing the repetition rate of the TS system to 120 Hz or allowing to obtain four profiles with tight timing in order to measure fast transient events in the plasma.
Primary author
Petr Böhm
Co-authors
Mr
Ales Havranek
(Institute of Plasma Physics of the CAS, Czech Republic)
Mr
David Sestak
(Institute of Plasma Physics of the CAS, Czech Republic)
Martin Hron
(Institute of Plasma Physics of the CAS, Czech Republic)
Dr
Milan Aftanas
(Institute of Plasma Physics of the CAS, Czech Republic)
Miroslav Šos
(Institute of Plasma Physics of the CAS, Czech Republic)
Petra Bílková
(Institute of Plasma Physics of the CAS, Czech Republic)
Dr
Radomir Panek
(Institute of Plasma Physics of the CAS, Czech Republic)
Vladimír Weinzettl
(Institute of Plasma Physics of the CAS, Czech Republic)
