Lithium beam diagnostics at ASDEX Upgrade
The lithium beam emission spectroscopy (Li-BES) has become a powerful diagnostic to resolve the plasma edge density in a fusion experiment with high temporal and spatial resolution. Over the past decades the TU Wien has developed the foundations of this diagnostics by providing an accurate atomic database and developing an accurate modeling of the beam attenuation in the plasma. Up to this date TU Wien contributes to the routine operation of Li-BES at the Tokamak experiment ASDEX Upgrade (IPP Garching). Within H2020 the Li-BES diagnostics at ASDEX Upgrade has been upgraded with the help from TU Wien by installing a new observation system M. Willensdorfer et al., Plasma Physics and Controlled Fusion 56 (2014) 025008.
The resulting gain in photon flux now allows the plasma edge density to be determined with an advanced level of accuracy. Furthermore, electron density fluctuations can be performed using Li- BES. The Li-BES is well suited to characterize electron density turbulence in the scrape off layer (SOL) with decreasing sensitivity towards the plasma core and an excellent tool to study transport phenomena in the SOL over a wide range of plasma parameters due to its robustness and routine usage. Together with interferometry diagnostics the Li-BES is now part of the integrated data analysis (IDA) and routinely used for the evaluation of electron density profiles in ASDEX Upgrade M. Willensdorfer et al., Journal of Nuclear Materials 463 (2015) 1091.
M. Willensdorfer, E. Wolfrum, R. Fischer, J. Schweinzer, M. Sertoli, B. Sieglin, G. Veres, and F. Aumayr
Improved chopping of a lithium beam for plasma edge diagnostic at ASDEX Upgrade
Review of Scientific Instruments 83 (2012) 023501 (7 pages)
H. D. Falter, M. Proschek, S. Menhart, F. Aumayr, HP. Winter, D. Ciric, S. Cox , A. Dines, D. Godden, N. Hawkes and T.T.C. Jones
Helium doped hydrogen or deuterium beam as cost effective and simple tool for plasma spectroscopy
Review Scientific Instruments 71 (2000) 3723
R. Brandenburg, J. Schweinzer, S. Fiedler, F. Aumayr and HP. Winter
Modelling of fast neutral Li beams for fusion edge plasma diagnostics
Plasma Physics and Controlled Fusion 41 (1999) 471 - 484
S. Fiedler, R. Brandenburg, J. Baldzuhn, K. McCormick, F. Aumayr, J. Schweinzer, HP. Winter, W7-AS and ASDEX-Upgrade team
Edge plasma diagnostics on W7-AS and ASDEX-Upgrade using fast Li beams
Journal of Nuclear Materials 266-269 (1999) 1279 - 1284
E. Wolfrum, F. Aumayr, D. Wutte, HP. Winter, E. Hintz, D. Rusbüldt and R.P. Schorn
Fast lithium - beam spectroscopy of tokamak edge plasmas
Review of Scientific Instruments 64 (1993) 2285 - 2292