Conference paper
Diagnosis of energetic ions and ion composition in fusion plasmas by collective Thomson scattering of mm-waves
In fusion plasmas, the dominant heating source will be fusion generated energetic ions slowing down in the plasma. The same ions can also drive waves and instabilities in the plasma. Their distribution in velocity and in space has major impact on plasma dynamics, and plasma dynamics in turn affects the energetic ion distributions.
The dynamics of energetic ions is thus important to measure in order to understand fusion plasmas, and important to monitor as part of input to plasma control. The collective Thomson scattering of millimeter waves has proven to be a valuable means of diagnosing energetic ion distributions in fusion plasmas1,2.
A beam of mm-waves with a diameter of 5–10 cm and a power of 150–600 kW is sent through the plasma, and radiation scattered from this probe beam by the microscopic fluctuations in the plasma is detected. These microscopic fluctuations are in part induced by the ion motion and the fluctuations and hence the scattered radiation is thus sensitive to the ion distribution.
This permits the fast ion distribution to be inferred from the detected scattered radiation. Dynamics of the fast ions is measured, and phenomena related to plasma instabilities observed.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2012 |
| Pages: | 7C-10-7C-10 |
| Proceedings: | 2012 39th IEEE International Conference on Plasma Science (ICOPS) |
| ISBN: | 1457721279 , 1457721287 , 1457721295 , 9781457721274 , 9781457721281 and 9781457721298 |
| ISSN: | 07309244 and 25767208 |
| Types: | Conference paper |
| DOI: | 10.1109/PLASMA.2012.6384084 |
| ORCIDs: | Korsholm, Søren Bang , Leipold, Frank , Michelsen, Poul , Nielsen, Stefan Kragh , Salewski, Mirko and Stejner Pedersen, Morten |
Fluctuations Ions Microscopy Plasma measurements Plasmas Scattering Thomson scattering Tokamak devices Velocity measurement cyclotron motion energetic ions diagnosis fuel ion density fusion generated energetic ions fusion plasmas heating source ion Bernstein waves ion composition microscopic fluctuations millimetre wave propagation mm-waves scattering plasma Bernstein waves plasma control plasma density plasma diagnostics plasma dynamics plasma fluctuations plasma heating plasma instability plasma toroidal confinement plasma transport processes power 150 kW to 600 kW radiation scattering velocity distribution
