an overview of recent ae stability measurements on jet · jet ae antenna | itpa-ep oct 2020 | 4 b 0...

An overview of recent AE stability

measurements on JET

R.A. Tinguely et al

ITPA-EP Meeting, October 2020

With contributions from

N. Fil2, P. Puglia3, M. Porkolab1, S. Dowson2, N. Dreval4,

R. Dumont5, A. Dvornova5, A. Fasoli3, M. Fitzgerald2,

V. Guillemot6, G.T.A. Huysmans5, Y. Kazakov7, D. Keeling2,

Z. Lin8, M. Maslov2, M. Nocente9,10, J. Ongena7, S. Sharapov2,

Ž. Štancar2, D. Testa3, and JET Contributors*

1 MIT Plasma Science and Fusion Center, Cambridge, USA2 CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB, UK3 EPFL Swiss Plasma Center, Lausanne, Switzerland4 Institute of Plasma Physics, NSC KIPT, 310108 Kharkov, Ukraine5 CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France6 ESPCI, 75231 Paris Cedex 05, France7 LPP-ERM/KMS, TEC Partner, 1000 Brussels, Belgium8 Department of Physics and Astronomy, UC Irvine, Irvine, USA9 Dipartimento di Fisica, Università di Milano-Bicocca, 20126 Milan, Italy10 IPST, National Research Council, 20125, Milan, Italy* See author list of E. Joffrin et al 2019 Nucl. Fusion 59 112021

JET AE Antenna | ITPA-EP Oct 2020 | 2

AE antenna actively probes stable AEs

• Eight in-vessel, toroidally-spaced antennas in JET

• Current < 10 A; independent phasing → |n| < 20

• Scan frequency ranges 25-50, 75-150, 125-250 kHz

Panis NF 2010

P. Puglia et al 2016 Nucl. Fusion 56 112020


Database of 5000+ stable AEs:Frequencies, damping rates, toroidal mode numbers

R A Tinguely et al 2020 Plasma Phys. Control. Fusion 62 115002

R A Tinguely et al 2020 Nucl. Fusion In review


B0 < 3.7 T

IP < 2.8 MA

ne0 < 1020 m-3

Te0 < 7 keV

PNBI < 7 MW*

PICRH < 7 MW

Outline: Novel measurements

1. Simultaneous unstable (n = 2-5) and stable (n = 6?) TAEs

• TRANSP run in progress (JPN 94700)

• Good comparison with JPN 94701 [S Mazzi 2020 Submitted]

2. Real-time tracking of stable AE during ~20 MW NBI heating

• Gyrokinetic simulations underway with GTC [Z Lin 1998 Science]

• Hopeful for analytic calculations a la [J Seo 2020 NF]

3. TAEs monitored from destabilization through stabilization

• TRANSP run in progress

• Hopeful for similar/improved results in the JET DT campaign

Bonus:

• Database trends [Tinguely 2020 PPCF 62 115002]

• Plasma-antenna coupling [Tinguely 2020 NF In review]


JPN 94700:

Simultaneous measurements of

stable and unstable AEs


JPN 94700: 3-ion ICRF scenario D-(DNBI)-3HeAE antenna with even phasing: |n| = 0,2,4…


n = 2-5 TAEs destabilized by NBI+RF, marginal n = 6 TAE seen by one probe


JPN 94700: stable AE measurements, f ~ 245 kHz, −𝜸/𝝎𝟎 ~ 1-2%, n = 6?


JPN 94703:

Measurement of a stable AE

during high NBI power


JPN 94703 vs 95683: D-DNBI-3HeNBI / RF (MW) : 19-21 / 4.4 vs 18.5 / 5.5


n = 2 (~185 kHz)

n = 3 (~205 kHz)

n = 4 (~223 kHz)

JPN 95683: unstable n = 2-4 TAEs,18.5 MW NBI + 5.5 MW RF


JPN 94703: stable AE tracked during 19-21 MW NBI + 4.4 MW RF

(odd antenna phasing)


JPN 94703: Marginally-stable TAEs,low damping rates < 0.5%, |n| ~ 0-5


JPN 96851:

Measurement of AE stabilization

in energetic particle experiments


JPN 96851: ~10 MW NBI + ~4 MW RF


TAEs (n = 2-6) destabilized by NBI+RF, then AE antenna tracks stable mode


JPN 96851: damping rate ~ 1% only ~300 ms after end of RF, n = 0 GAE?


Unstable TAEs

Summary: Novel measurements

1. Simultaneous unstable (n = 2-5) and stable (n = 6?) TAEs

• TRANSP run in progress (JPN 94700)

• Good comparison with JPN 94701 [S Mazzi 2020 Submitted]

2. Real-time tracking of stable AE during ~20 MW NBI heating

• Gyrokinetic simulations underway with GTC [Z Lin 1998 Science]

• Hopeful for analytic calculations a la [J Seo 2020 NF]

3. TAEs monitored from destabilization through stabilization

• TRANSP run in progress

• Hopeful for similar/improved results in the JET DT campaign


an overview of recent ae stability measurements on jet · jet ae antenna | itpa-ep oct 2020 | 4 b 0...

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