[Table of Contents]

Plasma and Fusion Research

Volume 8, 2502071 (2013)

Overview Articles

Study of Interaction between Fast Ions and MHD Instabilities by Fusion Product Measurements in Joint European Torus
Vasily G. KIPTILY1), Sergei E. SHARAPOV1), Thomas GASSNER2), Christian PEREZ VON THUN3,4), Simon D. PINCHES5), Barry ALPER1), Ed CECIL6), Douglass DARROW7), Victor GOLOBOROD'KO2,8), Carl HELLESEN9), Joelle MAILLOUX1), William MORRIS1), Victor YAVORSKIJ2,8) and JET-EFDA Contributors
JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon, United Kingdom
1)
EURATOM / CCFE Fusion Association, Culham Science Centre, Abingdon, United Kingdom
2)
Euratom/OEAW Association, ITP, University of Innsbruck, Austria
3)
JET-EFDA Close Support Unit, Culham Science Centre, Abingdon, United Kingdom
4)
Max-Planck-Institut für Plasmaphysik, EURATOM-Association IPP, Garching, Germany
5)
ITER Organization, Route de Vinon-sur-Verdon, 13115 St. Paul-lez-Durance, France
6)
Colorado School of Mines, 1500 Illinois Street, Golden, Colorado, USA
7)
Princeton Plasma Physics Laboratory, Princeton, New Jersey, USA
8)
Institute for Nuclear Research, Kiev, Ukraine
9)
Department of Physics and Astronomy, Uppsala University, BOX 516, Uppsala, Sweden
(Received 28 November 2012 / Accepted 10 April 2013 / Published 19 June 2013)

Abstract

Fast ion redistribution and losses caused by plasma disruptions, Toroidal Alfvén Eigenmodes (TAE) and fishbones are measured with a suite of improved gamma-ray diagnostics, Neutral Particle Analyser (NPA), neutron spectrometry, Faraday Cups and a Scintillator Probe (SP). Fast ion populations in the MeV energy range were generated in fusion reactions and were also produced by 3rd harmonic Ion Cyclotron Resonance Heating (ICRH). Significant fast ion losses preceding plasma disruptions were often detected by SP in discharges with high βN. These losses were caused by the m = 2 / n = 1 kink mode and typically occurred at the time of thermal quench, before the current quench. Core-localised TAE modes inside the q = 1 radius causing redistribution of the fast ions in the resonance energy range were directly measured for the first time with the gamma-ray camera, confirming that the TAE instability expels fast ions from inside the q = 1 radius and triggers the monster sawtooth crashes. Energy and pitch angle resolved SP measurements of lost fusion products in the MeV energy range were found to correlate with low-frequency fishbone oscillations driven by 100 keV beam ions. The origin and amplitude of these non-resonant losses are investigated.

Keywords

tokamak plasma, fusion product, fast ion, MHD instability, diagnostics, fast ion and MHD modeling

DOI: 10.1585/pfr.8.2502071

Full Text

PDF format (2.2Mbytes) PDF Download

References

  • [1] V.G. Kiptily et al., Nucl. Fusion 49, 065030 (2009).
  • [2] V.G. Kiptily et al., Nucl. Fusion 42, 999 (2002).
  • [3] V.G. Kiptily et al., Nucl. Fusion 45, L21 (2005).
  • [4] V.I. Afanasyev et al., Rev. Sci. Instrum. 74, 2338 (2003).
  • [5] C. Hellesen et al., Nucl. Fusion 50, 022001 (2010).
  • [6] D.S. Darrow et al., Rev. Sci. Instrum. 75, 3566 (2004).
  • [7] S. Baumel et al., Rev. Sci. Instrum. 75, 3563 (2004).
  • [8] J. Mailloux et al., in Fusion Energy 2010 (Proc. 23rd Int. Conf. Daejeon, 2010) (Vienna: IAEA) CD-ROM file EXC/1-4 and http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/papers/exc_1-4.pdf http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/html/node41.htm#10767
  • [9] A. Werner, A. Weller and D.S. Darrow, Rev. Sci. Instrum. 72, 780 (2001).
  • [10] N.N. Gorelenkov et al., Phys. Plasmas 10, 713 (2003).
  • [11] M. Saigusa et al., Plasma Phys. Control. Fusion 40, 1647 (1998).
  • [12] P. Sandquist et al., Phys. Plasma 14, 122506 (2007).
  • [13] G.J. Kramer et al., Phys. Rev. Lett. 92, 015001 (2004).
  • [14] W.W. Heidbrink et al., Nucl. Fusion 39, 1369 (1999).
  • [15] S. Bernabei et al., Nucl. Fusion 41, 513 (2001).
  • [16] S. Bernabei et al., Phys. Rev. Lett. 84, 1212 (2000).
  • [17] S.D. Pinches et al., Plasma Phys. Control. Fusion 46, B187 (2004).
  • [18] S.E. Sharapov et al., Nucl. Fusion 45, 1168 (2005).
  • [19] F. Nabais et al., Nucl. Fusion 50, 084021 (2010).
  • [20] T. Gassner et al., Phys. Plasmas 19, 032115 (2012).
  • [21] S.D. Pinches et al., Comput. Phys. Commun. 111, 133 (1998).
  • [22] W. Kerner et al., J. Comput. Phys. 142, 271 (1998).
  • [23] G.T.A. Huysmans, J.P. Goeldbloed and W. Kerner, Proc. CP90 Conf. Computational Physics, Amsterdam, the Netherlands, September 10-13, 1990, p. 371, World Scientific Publ. Co. (1991).
  • [24] K. McGuire et al., Phys. Rev. Lett. 50, 891 (1983).
  • [25] W.W. Heidbrink et al., Phys. Rev. Lett. 57, 835 (1986).
  • [26] B. Coppi, S. Miglioulo and F. Porcelli, Phys. Fluids 31, 1630 (1988).
  • [27] D. Borba et al., Nucl. Fusion 40, 775 (2000).
  • [28] B. Coppi and F. Porcelli, Fusion Technol. 13, 447 (1988).
  • [29] C. Perez von Thun et al., Nucl. Fusion 50, 084009 (2010).
  • [30] J. Hedin et al., Nucl. Fusion 42, 52 (2002).

This paper may be cited as follows:

Vasily G. KIPTILY, Sergei E. SHARAPOV, Thomas GASSNER, Christian PEREZ VON THUN, Simon D. PINCHES, Barry ALPER, Ed CECIL, Douglass DARROW, Victor GOLOBOROD'KO, Carl HELLESEN, Joelle MAILLOUX, William MORRIS, Victor YAVORSKIJ and JET-EFDA , Plasma Fusion Res. 8, 2502071 (2013).