Published May 2000 | Version v1
Journal article

Fast particles-wave interaction in the Alfven frequency range on the Joint European Torus tokamak

  • 1. Physics Department and PSFC, MIT, 175 Albany Street, Cambridge, Massachusetts 02139 (United States)
  • 2. Association EURATOM/IST, Av. Rovisto Paris, 1096 Lisbon, (Portugal)
  • 3. JET Joint Undertaking, Abingdon, OX14 3EA, (United Kingdom)
  • 4. Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)
  • 5. Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)
  • 6. Alfven Laboratory, Royal Institute of Technology, SE-100 44, Stockholm, (Sweden)

Description

Wave-particle interaction phenomena in the Alfven Eigenmode (AE) frequency range are investigated at the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)] using active and passive diagnostic methods. Fast particles are generated by neutral beam injection, ion cyclotron resonance heating, and fusion reactions. External antennas are used to excite stable AEs and measure fast particle drive and damping separately. Comparisons with numerical calculations lead to an identification of the different damping mechanisms. The use of the active AE diagnostic system to generate control signals based on the proximity to marginal stability limits for AE and low-frequency magnetohydrodynamic (MHD) modes is explored. Signatures of the different nonlinear regimes of fast particle driven AE instabilities predicted by theory are found in the measured spectra. The diagnostic use of AE measurements to get information both on the plasma bulk and the fast particle distribution is assessed. (c) 2000 American Institute of Physics

Additional details

Publishing Information

Journal Title
Physics of Plasmas
Journal Volume
7
Journal Issue
5
Journal Page Range
p. 1816-1824
ISSN
1070-664X
CODEN
PHPAEN