Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S

S.K. Nielsen, M. Salewski, H. Bindslev, A. Bürger, V. Furtula, M. Kantor, S.B. Korsholm, H.R. Koslowski, A. Krämer-Flecken, F. Leipold, F. Meo, P.K. Michelsen, D. Moseev, J.W. Oosterbeek, M. Stejner, E. Westerhof

Research output: Contribution to journalArticleAcademicpeer-review

28 Citations (Scopus)

Abstract

Experimental investigations of sawteeth interaction with fast ions measured by collective Thomson scattering on TEXTOR are presented. Time-resolved measurements of localized 1D fast-ion distribution functions allow us to study fast-ion dynamics during several sawtooth cycles. Sawtooth oscillations interact strongly with the fast-ion population in a wide range of plasma parameters. Part of the ion phase space density oscillates out of phase with the sawtooth oscillation during hydrogen neutral beam injection (NBI). These oscillations most likely originate from fast hydrogen ions with energies close to the full injection energy. At lower energies passing fast ions in the plasma centre are strongly redistributed at the time of sawtooth collapse but no redistribution of trapped fast ions is observed. The redistribution of fast ions from deuterium NBI in the plasma centre is found to vary throughout velocity space. The reduction is most pronounced for passing ions. We find no evidence of inverted sawteeth outside the sawtooth inversion surface in the fast-ion distribution function.
Original languageEnglish
Article number063014
Pages (from-to)063014-1/8
Number of pages8
JournalNuclear Fusion
Volume51
Issue number6
DOIs
Publication statusPublished - 2011

Fingerprint

Thomson scattering
oscillations
ions
beam injection
ion distribution
neutral beams
distribution functions
space density
hydrogen ions
energy
deuterium
time measurement
inversions
injection
cycles
hydrogen

Cite this

Nielsen, S. K., Salewski, M., Bindslev, H., Bürger, A., Furtula, V., Kantor, M., ... Westerhof, E. (2011). Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S. Nuclear Fusion, 51(6), 063014-1/8. [063014]. https://doi.org/10.1088/0029-5515/51/6/063014
Nielsen, S.K. ; Salewski, M. ; Bindslev, H. ; Bürger, A. ; Furtula, V. ; Kantor, M. ; Korsholm, S.B. ; Koslowski, H.R. ; Krämer-Flecken, A. ; Leipold, F. ; Meo, F. ; Michelsen, P.K. ; Moseev, D. ; Oosterbeek, J.W. ; Stejner, M. ; Westerhof, E. / Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S. In: Nuclear Fusion. 2011 ; Vol. 51, No. 6. pp. 063014-1/8.
@article{6f546fb127d14d8e9c072950f849286e,
title = "Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S",
abstract = "Experimental investigations of sawteeth interaction with fast ions measured by collective Thomson scattering on TEXTOR are presented. Time-resolved measurements of localized 1D fast-ion distribution functions allow us to study fast-ion dynamics during several sawtooth cycles. Sawtooth oscillations interact strongly with the fast-ion population in a wide range of plasma parameters. Part of the ion phase space density oscillates out of phase with the sawtooth oscillation during hydrogen neutral beam injection (NBI). These oscillations most likely originate from fast hydrogen ions with energies close to the full injection energy. At lower energies passing fast ions in the plasma centre are strongly redistributed at the time of sawtooth collapse but no redistribution of trapped fast ions is observed. The redistribution of fast ions from deuterium NBI in the plasma centre is found to vary throughout velocity space. The reduction is most pronounced for passing ions. We find no evidence of inverted sawteeth outside the sawtooth inversion surface in the fast-ion distribution function.",
author = "S.K. Nielsen and M. Salewski and H. Bindslev and A. B{\"u}rger and V. Furtula and M. Kantor and S.B. Korsholm and H.R. Koslowski and A. Kr{\"a}mer-Flecken and F. Leipold and F. Meo and P.K. Michelsen and D. Moseev and J.W. Oosterbeek and M. Stejner and E. Westerhof",
year = "2011",
doi = "10.1088/0029-5515/51/6/063014",
language = "English",
volume = "51",
pages = "063014--1/8",
journal = "Nuclear Fusion",
issn = "0029-5515",
publisher = "Institute of Physics",
number = "6",

}

Nielsen, SK, Salewski, M, Bindslev, H, Bürger, A, Furtula, V, Kantor, M, Korsholm, SB, Koslowski, HR, Krämer-Flecken, A, Leipold, F, Meo, F, Michelsen, PK, Moseev, D, Oosterbeek, JW, Stejner, M & Westerhof, E 2011, 'Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S', Nuclear Fusion, vol. 51, no. 6, 063014, pp. 063014-1/8. https://doi.org/10.1088/0029-5515/51/6/063014

Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S. / Nielsen, S.K.; Salewski, M.; Bindslev, H.; Bürger, A.; Furtula, V.; Kantor, M.; Korsholm, S.B.; Koslowski, H.R.; Krämer-Flecken, A.; Leipold, F.; Meo, F.; Michelsen, P.K.; Moseev, D.; Oosterbeek, J.W.; Stejner, M.; Westerhof, E.

In: Nuclear Fusion, Vol. 51, No. 6, 063014, 2011, p. 063014-1/8.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Dynamics of fast ions during sawtooth oscillations in the TEXTOR tokamak measured by collective Thomson scattering S

AU - Nielsen, S.K.

AU - Salewski, M.

AU - Bindslev, H.

AU - Bürger, A.

AU - Furtula, V.

AU - Kantor, M.

AU - Korsholm, S.B.

AU - Koslowski, H.R.

AU - Krämer-Flecken, A.

AU - Leipold, F.

AU - Meo, F.

AU - Michelsen, P.K.

AU - Moseev, D.

AU - Oosterbeek, J.W.

AU - Stejner, M.

AU - Westerhof, E.

PY - 2011

Y1 - 2011

N2 - Experimental investigations of sawteeth interaction with fast ions measured by collective Thomson scattering on TEXTOR are presented. Time-resolved measurements of localized 1D fast-ion distribution functions allow us to study fast-ion dynamics during several sawtooth cycles. Sawtooth oscillations interact strongly with the fast-ion population in a wide range of plasma parameters. Part of the ion phase space density oscillates out of phase with the sawtooth oscillation during hydrogen neutral beam injection (NBI). These oscillations most likely originate from fast hydrogen ions with energies close to the full injection energy. At lower energies passing fast ions in the plasma centre are strongly redistributed at the time of sawtooth collapse but no redistribution of trapped fast ions is observed. The redistribution of fast ions from deuterium NBI in the plasma centre is found to vary throughout velocity space. The reduction is most pronounced for passing ions. We find no evidence of inverted sawteeth outside the sawtooth inversion surface in the fast-ion distribution function.

AB - Experimental investigations of sawteeth interaction with fast ions measured by collective Thomson scattering on TEXTOR are presented. Time-resolved measurements of localized 1D fast-ion distribution functions allow us to study fast-ion dynamics during several sawtooth cycles. Sawtooth oscillations interact strongly with the fast-ion population in a wide range of plasma parameters. Part of the ion phase space density oscillates out of phase with the sawtooth oscillation during hydrogen neutral beam injection (NBI). These oscillations most likely originate from fast hydrogen ions with energies close to the full injection energy. At lower energies passing fast ions in the plasma centre are strongly redistributed at the time of sawtooth collapse but no redistribution of trapped fast ions is observed. The redistribution of fast ions from deuterium NBI in the plasma centre is found to vary throughout velocity space. The reduction is most pronounced for passing ions. We find no evidence of inverted sawteeth outside the sawtooth inversion surface in the fast-ion distribution function.

U2 - 10.1088/0029-5515/51/6/063014

DO - 10.1088/0029-5515/51/6/063014

M3 - Article

VL - 51

SP - 063014-1/8

JO - Nuclear Fusion

JF - Nuclear Fusion

SN - 0029-5515

IS - 6

M1 - 063014

ER -