Recent JET experiments on Alfven eigenmodes with intermediate toroidal mode numbers: measurements and modelling of n=3 toroidal Alfven eigenmodes with the TAEFL code

Journal Article · Sat Jan 01 04:00:00 EST 2011 · Nuclear Fusion

DOI:https://doi.org/10.1088/0029-5515/51/4/043009· OSTI ID:1036629

Testa, D ^[1]; Spong, Donald A ^[2]; Panis, T ^[1]; Blanchard, P ^[1]; Fasoli, A ^[1]

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1. CRPP, Switzerland
2. ORNL

This paper reports the results of recent experiments performed on the JET tokamak on Alfven eigenmodes (AEs) with toroidal mode number (n) in the range n = 3-15. The stability properties of these medium-n AEs are investigated experimentally using a new set of compact in-vessel antennas, providing a direct and real-time measurement of the frequency, damping rate and amplitude for each individual toroidal mode number. We report here the quantitative analysis of the measurements of the damping rate for stable n = 3 toroidal AEs as a function of the edge plasma elongation, and the theoretical analysis of these data with the TAEFL code. The TAEFL results are in excellent qualitative agreement with the measurements, reproducing well the experimental scaling of increasing damping rate versus increasing edge elongation, and in many cases are also quantitatively correct, with a difference with respect to the measurements below 30%, particularly for magnetic configurations that have a larger edge magnetic shear.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1036629
• Journal Information: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 4 Vol. 51; ISSN 0029-5515
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLITUDES
ANTENNAS
DAMPING
ELONGATION
JET TOKAMAK
PLASMA
SHEAR
STABILITY