Charge exchange spectroscopy as a fast ion diagnostic on TEXTOR
- FOM-Rijnhuizen, EURATOM-FOM, NL-3430 BE Nieuwegein (Netherlands)
- Association EURATOM-Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, DK-4000 Roskilde (Denmark)
- Forschungszentrum Juelich, EURATOM-FZJ, D-52424 Juelich (Germany)
An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam for active spectroscopy, injected counter the direction in which fast ions injected by the first beam are circulating, we can simultaneously measure a fast ion tail on the blue wing of the D{sub {alpha}} spectrum while the beam emission spectrum is Doppler shifted to the red wing. An analysis combining the two parts of the spectrum offers possibilities to improve the accuracy of the absolute (fast) ion density profiles. Fast beam modulation or passive viewing lines cannot be used for background subtraction on this diagnostic setup and therefore the background has to be modeled and fitted to the data together with a spectral model for the slowing down feature. The analysis of the fast ion D{sub {alpha}} spectrum obtained with the new diagnostic is discussed.
- OSTI ID:
- 21266511
- Journal Information:
- Review of Scientific Instruments, Vol. 79, Issue 10; Conference: HTPD08: 17. topical conference on high-temperature plasma diagnostics, Albuquerque, NM (United States), 11-15 May 2008; Other Information: DOI: 10.1063/1.2955575; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extended fast-ion D-alpha diagnostic on DIII-D
A new fast-ion D{sub {alpha}} diagnostic for DIII-D