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

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    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",

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    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 -