Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating

T. Hellsten, T. Johnson, D. Van Easter, E. Lerche, Y. Lin, M.-L. Mayoral, J. Ongena, G. Calabro, K. Crombe, D. Frigione, C. Giroud, M. Lennholm, P. Mantica, M.F.F. Nave, V. Naulin, C. Sozzi, W. Studholme, Tuomas Tala, T. Versloot, JET-EFDA Contributors

Research output: Contribution to journalArticleScientificpeer-review

8 Citations (Scopus)

Abstract

The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constant angular rotation. The core rotation is stronger in magnitude than observed for scenarios with dominating ion cyclotron absorption. Two scenarios are considered: the inverted mode conversion scenarios and heating at the second harmonic 3He cyclotron resonance in H plasmas. In the latter case, electron absorption of the fast magnetosonic wave by transit time magnetic pumping and electron Landau damping (TTMP/ELD) is the dominating absorption mechanism. Inverted mode conversion is done in (3He)-H plasmas where the mode converted waves are essentially absorbed by electron Landau damping. Similar rotation profiles are seen when heating at the second harmonic cyclotron frequency of 3He and with mode conversion at high concentrations of 3He. The magnitude of the counter-rotation is found to decrease with an increasing plasma current. The correlation of the rotation with the electron temperature is better than with coupled power, indicating that for these types of discharges the dominating mechanism for the rotation is related to indirect effects of electron heat transport, rather than to direct effects of ICRF heating. There is no conclusive evidence that mode conversion in itself affects rotation for these discharges.
Original languageEnglish
Article number074007
JournalPlasma Physics and Controlled Fusion
Volume54
Issue number7
DOIs
Publication statusPublished - 2012
MoE publication typeA1 Journal article-refereed

Fingerprint

Cyclotron resonance
cyclotron resonance
Plasmas
Heating
heating
Electrons
Ions
Cyclotrons
ions
electrons
cyclotrons
Landau damping
magnetic pumping
counter rotation
Electron absorption
Damping
harmonics
plasma currents
cyclotron frequency
transit time

Cite this

Hellsten, T., Johnson, T., Van Easter, D., Lerche, E., Lin, Y., Mayoral, M-L., ... Contributors, JET-EFDA. (2012). Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating. Plasma Physics and Controlled Fusion, 54(7), [074007]. https://doi.org/10.1088/0741-3335/54/7/074007
Hellsten, T. ; Johnson, T. ; Van Easter, D. ; Lerche, E. ; Lin, Y. ; Mayoral, M.-L. ; Ongena, J. ; Calabro, G. ; Crombe, K. ; Frigione, D. ; Giroud, C. ; Lennholm, M. ; Mantica, P. ; Nave, M.F.F. ; Naulin, V. ; Sozzi, C. ; Studholme, W. ; Tala, Tuomas ; Versloot, T. ; Contributors, JET-EFDA. / Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating. In: Plasma Physics and Controlled Fusion. 2012 ; Vol. 54, No. 7.
@article{73d8a2a26e7c4f5981b444b0d9bb72da,
title = "Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating",
abstract = "The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constant angular rotation. The core rotation is stronger in magnitude than observed for scenarios with dominating ion cyclotron absorption. Two scenarios are considered: the inverted mode conversion scenarios and heating at the second harmonic 3He cyclotron resonance in H plasmas. In the latter case, electron absorption of the fast magnetosonic wave by transit time magnetic pumping and electron Landau damping (TTMP/ELD) is the dominating absorption mechanism. Inverted mode conversion is done in (3He)-H plasmas where the mode converted waves are essentially absorbed by electron Landau damping. Similar rotation profiles are seen when heating at the second harmonic cyclotron frequency of 3He and with mode conversion at high concentrations of 3He. The magnitude of the counter-rotation is found to decrease with an increasing plasma current. The correlation of the rotation with the electron temperature is better than with coupled power, indicating that for these types of discharges the dominating mechanism for the rotation is related to indirect effects of electron heat transport, rather than to direct effects of ICRF heating. There is no conclusive evidence that mode conversion in itself affects rotation for these discharges.",
author = "T. Hellsten and T. Johnson and {Van Easter}, D. and E. Lerche and Y. Lin and M.-L. Mayoral and J. Ongena and G. Calabro and K. Crombe and D. Frigione and C. Giroud and M. Lennholm and P. Mantica and M.F.F. Nave and V. Naulin and C. Sozzi and W. Studholme and Tuomas Tala and T. Versloot and JET-EFDA Contributors",
year = "2012",
doi = "10.1088/0741-3335/54/7/074007",
language = "English",
volume = "54",
journal = "Plasma Physics and Controlled Fusion",
issn = "0741-3335",
publisher = "Institute of Physics IOP",
number = "7",

}

Hellsten, T, Johnson, T, Van Easter, D, Lerche, E, Lin, Y, Mayoral, M-L, Ongena, J, Calabro, G, Crombe, K, Frigione, D, Giroud, C, Lennholm, M, Mantica, P, Nave, MFF, Naulin, V, Sozzi, C, Studholme, W, Tala, T, Versloot, T & Contributors, JET-EFDA 2012, 'Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating', Plasma Physics and Controlled Fusion, vol. 54, no. 7, 074007. https://doi.org/10.1088/0741-3335/54/7/074007

Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating. / Hellsten, T.; Johnson, T.; Van Easter, D.; Lerche, E.; Lin, Y.; Mayoral, M.-L.; Ongena, J.; Calabro, G.; Crombe, K.; Frigione, D.; Giroud, C.; Lennholm, M.; Mantica, P.; Nave, M.F.F.; Naulin, V.; Sozzi, C.; Studholme, W.; Tala, Tuomas; Versloot, T.; Contributors, JET-EFDA.

In: Plasma Physics and Controlled Fusion, Vol. 54, No. 7, 074007, 2012.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating

AU - Hellsten, T.

AU - Johnson, T.

AU - Van Easter, D.

AU - Lerche, E.

AU - Lin, Y.

AU - Mayoral, M.-L.

AU - Ongena, J.

AU - Calabro, G.

AU - Crombe, K.

AU - Frigione, D.

AU - Giroud, C.

AU - Lennholm, M.

AU - Mantica, P.

AU - Nave, M.F.F.

AU - Naulin, V.

AU - Sozzi, C.

AU - Studholme, W.

AU - Tala, Tuomas

AU - Versloot, T.

AU - Contributors, JET-EFDA

PY - 2012

Y1 - 2012

N2 - The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constant angular rotation. The core rotation is stronger in magnitude than observed for scenarios with dominating ion cyclotron absorption. Two scenarios are considered: the inverted mode conversion scenarios and heating at the second harmonic 3He cyclotron resonance in H plasmas. In the latter case, electron absorption of the fast magnetosonic wave by transit time magnetic pumping and electron Landau damping (TTMP/ELD) is the dominating absorption mechanism. Inverted mode conversion is done in (3He)-H plasmas where the mode converted waves are essentially absorbed by electron Landau damping. Similar rotation profiles are seen when heating at the second harmonic cyclotron frequency of 3He and with mode conversion at high concentrations of 3He. The magnitude of the counter-rotation is found to decrease with an increasing plasma current. The correlation of the rotation with the electron temperature is better than with coupled power, indicating that for these types of discharges the dominating mechanism for the rotation is related to indirect effects of electron heat transport, rather than to direct effects of ICRF heating. There is no conclusive evidence that mode conversion in itself affects rotation for these discharges.

AB - The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constant angular rotation. The core rotation is stronger in magnitude than observed for scenarios with dominating ion cyclotron absorption. Two scenarios are considered: the inverted mode conversion scenarios and heating at the second harmonic 3He cyclotron resonance in H plasmas. In the latter case, electron absorption of the fast magnetosonic wave by transit time magnetic pumping and electron Landau damping (TTMP/ELD) is the dominating absorption mechanism. Inverted mode conversion is done in (3He)-H plasmas where the mode converted waves are essentially absorbed by electron Landau damping. Similar rotation profiles are seen when heating at the second harmonic cyclotron frequency of 3He and with mode conversion at high concentrations of 3He. The magnitude of the counter-rotation is found to decrease with an increasing plasma current. The correlation of the rotation with the electron temperature is better than with coupled power, indicating that for these types of discharges the dominating mechanism for the rotation is related to indirect effects of electron heat transport, rather than to direct effects of ICRF heating. There is no conclusive evidence that mode conversion in itself affects rotation for these discharges.

U2 - 10.1088/0741-3335/54/7/074007

DO - 10.1088/0741-3335/54/7/074007

M3 - Article

VL - 54

JO - Plasma Physics and Controlled Fusion

JF - Plasma Physics and Controlled Fusion

SN - 0741-3335

IS - 7

M1 - 074007

ER -