Fast measurement of plasma potential, temperature and density in theSOL of ASDEX Upgrade, compared with ESEL simulation

0352069 - ÚFP 2011 DE eng A - Abstrakt
Horáček, Jan - Adámek, Jiří - Müller, H. W. - Seidl, Jakub - Nielsen, A.H. - Rohde, V. - Mehlmann, F. - Ionita, C. - Havlíčková, Eva
Fast measurement of plasma potential, temperature and density in theSOL of ASDEX Upgrade, compared with ESEL simulation.
3rd EFDA Transport Topical Group Meeting combined with 15th EU-US Transport Task Force Meeting. Garching: Max Planck Society, 2010. O2.03-O2.03.
[EFDA Transport Topical Group Meeting combined with 15th EU-US Transport Task Force Meeting/3rd./. 07.10.2010-10.10.2010, Cordoba]
Výzkumný záměr: CEZ:AV0Z20430508
Klíčová slova: Tokamak * plasma * SOL turbulence * ESEL
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
http://ocs.ciemat.es/ttg2010abs/pdf/O2.03.pdf

This contribution focuses on fast (1 μs) and local (2-4 mm) measurement of plasma density, potential and electron temperature in the edge plasma of tokamak ASDEX Upgrade. The measurements were performed by a combined Langmuir/Ball-pen probe. First, steady-state radial profiles demonstrate credibility of the Ball-pen probe. We demonstrate that floating potential fluctuations measured by a Langmuir probe are dominated by plasma electron temperature rather than potential. Spatial and temporal scales are found consistent with expectations based on interchange-driven turbulence. Conditionally averaged signals found for both potential and density are also consistent, however, those for temperature show an unexpected 4 mm wide decrease by 10% at the very center of a blob. In the wall shadow, temperature measured by the swept Langmuir probe yields values 10 eV, whilst the Ball-pen temperature gradient is more steep and credible, dropping down to 1 eV.
Trvalý link: http://hdl.handle.net/11104/0191665