Design advances of the Core Plasma Thomson Scattering diagnostic for ITER.

0481464 - ÚFP 2018 RIV GB eng J - Článek v odborném periodiku
Scannell, R. - Maslov, M. - Naylor, G. - O’Gorman, T. - Kempenaars, M. - Carr, M. - Bílková, Petra - Böhm, Petr - Giudicotti, L. - Pasqualotto, R. - Bassan, M. - Vayakis, G. - Walsh, M. - Huxford, R.
Design advances of the Core Plasma Thomson Scattering diagnostic for ITER.
Journal of Instrumentation. Roč. 12, November (2017), č. článku C11010. ISSN 1748-0221. E-ISSN 1748-0221.
[International Symposium on Laser-Aided Plasma Diagnostics (LAPD2017) /18./. Prague, 24.09.2017-28.09.2017]
Institucionální podpora: RVO:61389021
Klíčová slova: Nuclear instruments and methods for hot plasma diagnostics * Plasma diagnostics - interferometry * spectroscopy and imaging
Obor OECD: 2.11 Other engineering and technologies
Impakt faktor: 1.258, rok: 2017
http://iopscience.iop.org/article/10.1088/1748-0221/12/11/C11010/pdf

The Core Plasma Thomson Scattering (CPTS) diagnostic on ITER performs measurements of the electron temperature and density profiles which are critical to the understanding of the ITER plasma. The diagnostic must satisfy the ITER project requirements, which translate to requirements on performance as well as reliability, safety and engineering. The implications
are particularly challenging for beam dump lifetime, the need for continuous active alignment of the diagnostic during operation, allowable neutron flux in the interspace and the protection of the first mirror from plasma deposition. The CPTS design has been evolving over a number of years. One recent improvement is that the collection optics have been modified to include freeform surfaces. These freeform surfaces introduce extra complexity to the manufacturing but provide greater
flexibility in the design. The greater flexibility introduced allows for example to lower neutron throughput or use fewer surfaces while improving optical performance. Performance assessment has shown that scattering from a 1064 nm laser will be sufficient to meet the measurement requirements, at least for the system at the start of operations. Optical transmission at lambda < 600 nm is
expected to degrade over the ITER lifetime due to fibre darkening and deposition on the first mirror. For this reason, it is proposed that the diagnostic should additionally include measurements of TS ‘depolarised light’ and a 1319 nm laser system. These additional techniques have different spectral and polarisation dependencies compared to scattering from a 1064 nm laser and hence provide
greater robustness into the inferred measurements of Te and ne in the core.
Trvalý link: http://hdl.handle.net/11104/0277231