Fast particle physics on ASDEX Upgrade

Slides:

Advertisements

Similar presentations

H-mode characterization for dominant ECR heating and comparison to dominant NBI or ICR heating F. Sommer PhD thesis advisor: Dr. Jörg Stober Academic advisor:

Advertisements

H. Weisen 1 21st IAEA FEC, Chengdu 2006 Peaked Density Profiles in Low Collisionality H-modes in JET, ASDEX Upgrade and TCV H. Weisen, C. Angioni, M. Maslov,

Institute of Interfacial Process Engineering and Plasma Technology Gas-puff imaging of blob filaments at ASDEX Upgrade TTF Workshop.

6 th ITPA MHD Topical Group Meeting combined with W60 IEA Workshop on Burning Plasmas Session II MHD Stability and Fast Particle Confinement General scope.

Cyclic MHD Instabilities Hartmut Zohm MPI für Plasmaphysik, EURATOM Association Seminar talk at the ‚Advanced Course‘ of EU PhD Network, Garching, September.

The Physics Base for ITER and DEMO Hartmut Zohm Max-Planck-Institut für Plasmaphysik, Garching, Germany EURATOM Association Hauptvortrag given at AKE DPG.

INTRODUCTION OF WAVE-PARTICLE RESONANCE IN TOKAMAKS J.Q. Dong Southwestern Institute of Physics Chengdu, China International School on Plasma Turbulence.

1 G.T. Hoang, 20th IAEA Fusion Energy Conference Euratom Turbulent Particle Transport in Tore Supra G.T. Hoang, J.F. Artaud, C. Bourdelle, X. Garbet and.

Fast ion effects on fishbones and n=1 kinks in JET simulated by a non-perturbative NOVA-KN code TH/5-2Rb N.N. Gorelenkov 1), C.Z.Cheng 1), V.G. Kiptily.

Physics of fusion power Lecture 11: Diagnostics / heating.

IAEA - FEC2004 // Vilamoura // // EX/4-5 // A. Staebler – 1 – A. Staebler, A.C.C Sips, M. Brambilla, R. Bilato, R. Dux, O. Gruber, J. Hobirk,

Overview of ASDEX Upgrade Results – Development of integrated operating scenarios for ITER The ASDEX Upgrade Team presented by Sibylle Günter MPI für Plasmaphysik,

D. Borba 1 21 st IAEA Fusion Energy Conference, Chengdu China 21 st October 2006 Excitation of Alfvén eigenmodes with sub-Alfvénic neutral beam ions in.

A. HerrmannITPA - Toronto /19 Filaments in the SOL and their impact to the first wall EURATOM - IPP Association, Garching, Germany A. Herrmann,

Computer simulations of fast frequency sweeping mode in JT-60U and fishbone instability Y. Todo (NIFS) Y. Shiozaki (Graduate Univ. Advanced Studies) K.

Nonlinear Frequency Chirping of Alfven Eigenmode in Toroidal Plasmas Huasen Zhang 1,2 1 Fusion Simulation Center, Peking University, Beijing , China.

ITPA Diagnostics 4/06 The Importance of Fast-Ion Profile Measurements in ITER W. Heidbrink Three examples from DIII-D Conclusion Fast-ion D  (FIDA) Technique.

J A Snipes, 6 th ITPA MHD Topical Group Meeting, Tarragona, Spain 4 – 6 July 2005 TAE Damping Rates on Alcator C-Mod Compared with Nova-K J A Snipes *,

Edge Localized Modes propagation and fluctuations in the JET SOL region presented by Bruno Gonçalves EURATOM/IST, Portugal.

TH/7-2 Radial Localization of Alfven Eigenmodes and Zonal Field Generation Z. Lin University of California, Irvine Fusion Simulation Center, Peking University.

XP NSTX Results Review Beam Modulation Effects on Ion Power Balance XP 737 P.W.Ross.

Particle Distribution Modification by TAE mode and Resonant Particle Orbits POSTECH 1, NFRI 1,2 M.H.Woo 1, C.M.Ryu 1, T.N.Rhee 1,,2.

Excitation of ion temperature gradient and trapped electron modes in HL-2A tokamak The 3 th Annual Workshop on Fusion Simulation and Theory, Hefei, March.

HAGIS Code Lynton Appel … on behalf of Simon Pinches and the HAGIS users CCFE is the fusion research arm of the United Kingdom Atomic Energy Authority.

Summary of MHD Topics 2nd IAEA Technical Meeting Theory of Plasma Instabilities Howard Wilson.

NSTX-U NSTX-U PAC-31 Response to Questions – Day 1 Summary of Answers Q: Maximum pulse length at 1MA, 0.75T, 1 st year parameters? –A1: Full 5 seconds.

1 Fast Ion D-Alpha (FIDA) measurements at ASDEX Upgrade B. Geiger, M. Garcia Munoz, W. W. Heidbrink, G. Tardini, V. Igochine, R. Fischer, R. Mc Dermott.

DIII-D SHOT #87009 Observes a Plasma Disruption During Neutral Beam Heating At High Plasma Beta Callen et.al, Phys. Plasmas 6, 2963 (1999) Rapid loss of.

2 The Neutral Particle Analyzer (NPA) on NSTX Scans Horizontally Over a Wide Range of Tangency Angles Covers Thermal ( keV) and Energetic Ion.

1 Confinement Studies on TJ-II Stellarator with OH Induced Current F. Castejón, D. López-Bruna, T. Estrada, J. Romero and E. Ascasíbar Laboratorio Nacional.

(National Institute for Fusion Science, Japan)

Electron inertial effects & particle acceleration at magnetic X-points Presented by K G McClements 1 Other contributors: A Thyagaraja 1, B Hamilton 2,

1Peter de Vries – ITBs and Rotational Shear – 18 February 2010 – Oxford Plasma Theory Group P.C. de Vries JET-EFDA Culham Science Centre Abingdon OX14.

Transport in three-dimensional magnetic field: examples from JT-60U and LHD Katsumi Ida and LHD experiment group and JT-60 group 14th IEA-RFP Workshop.

STUDIES OF NONLINEAR RESISTIVE AND EXTENDED MHD IN ADVANCED TOKAMAKS USING THE NIMROD CODE D. D. Schnack*, T. A. Gianakon**, S. E. Kruger*, and A. Tarditi*

Beam Voltage Threshold for Excitation of Compressional Alfvén Modes E D Fredrickson, J Menard, N Gorelenkov, S Kubota*, D Smith Princeton Plasma Physics.

Effect of Helical Magnetic Field Ripples on Energetic Particle Confinement in LHD Plasmas T.Saida, M.Sasao, M.Isobe 1, M.Nishiura 1, S.Murakami 2, K.Matsuoka.

The influence of non-resonant perturbation fields: Modelling results and Proposals for TEXTOR experiments S. Günter, V. Igochine, K. Lackner, Q. Yu IPP.

Summary of IAEA Theory Papers on Energetic Particle Physics Guoyong Fu.

1 Feature of Energy Transport in NSTX plasma Siye Ding under instruction of Stanley Kaye 05/04/09.

Simulations of NBI-driven Global Alfven Eigenmodes in NSTX E. V. Belova, N. N. Gorelenkov, C. Z. Cheng (PPPL) NSTX Results Forum, PPPL July 2006 Motivation:

Role of thermal instabilities and anomalous transport in the density limit M.Z.Tokar, F.A.Kelly, Y.Liang, X.Loozen Institut für Plasmaphysik, Forschungszentrum.

Advanced Tokamak Modeling for FIRE C. Kessel, PPPL NSO/PAC Meeting, University of Wisconsin, July 10-11, 2001.

Moving fast in fusion reactors: ASCOT – race track for fast ions

Ergodic heat transport analysis in non-aligned coordinate systems S. Günter, K. Lackner, Q. Yu IPP Garching Problems with non-aligned coordinates? Description.

1 NSTX EXPERIMENTAL PROPOSAL - OP-XP-712 Title: HHFW Power Balance Optimization at High B Field J. Hosea, R. Bell, S. Bernabei, L. Delgado-Aparicio, S.

T. Hellsten IAEA TM Meeting on Energetic Particles, San Diego 2003 T. Hellsten 1, T. Bergkvist 1, T.Johnson 1, M. Laxåback 1 and L.-G. Eriksson 2 1 Euratom-VR.

Initial Results from the Scintillator Fast Lost Ion Probe D. Darrow NSTX Physics Meeting February 28, 2005.

Effect of Energetic-Ion/Bulk-Plasma- driven MHD Instabilities on Energetic Ion Loss in the Large Helical Device Kunihiro OGAWA, Mitsutaka ISOBE, Kazuo.

Simulation of Turbulence in FTU M. Romanelli, M De Benedetti, A Thyagaraja* *UKAEA, Culham Sciance Centre, UK Associazione.

1 ASIPP Sawtooth Stabilization by Barely Trapped Energetic Electrons Produced by ECRH Zhou Deng, Wang Shaojie, Zhang Cheng Institute of Plasma Physics,

Energetic Particles Interaction with the Non-resonant Internal Kink in Spherical Tokamaks Feng Wang*, G.Y. Fu**, J.A. Breslau**, E.D. Fredrickson**, J.Y.

TH/7-1Multi-phase Simulation of Alfvén Eigenmodes and Fast Ion Distribution Flattening in DIII-D Experiment Y. Todo (NIFS, SOKENDAI) M. A. Van Zeeland.

6 th ITPA MHD Topical Group Meeting combined with W60 IEA Workshop on Burning Plasmas Summary Session II MHD Stability and Fast Particle Confinement chaired.

Hard X-rays from Superthermal Electrons in the HSX Stellarator Preliminary Examination for Ali E. Abdou Student at the Department of Engineering Physics.

Long Pulse High Performance Plasma Scenario Development for NSTX C. Kessel and S. Kaye - providing TRANSP runs of specific discharges S.

Energetic ion excited long-lasting “sword” modes in tokamak plasmas with low magnetic shear Speaker:RuiBin Zhang Advisor:Xiaogang Wang School of Physics,

NIMROD Simulations of a DIII-D Plasma Disruption S. Kruger, D. Schnack (SAIC) April 27, 2004 Sherwood Fusion Theory Meeting, Missoula, MT.

U NIVERSITY OF S CIENCE AND T ECHNOLOGY OF C HINA Influence of ion orbit width on threshold of neoclassical tearing modes Huishan Cai 1, Ding Li 2, Jintao.

M. Fitzgerald, S.E. Sharapov, P. Rodrigues2, D. Borba2

8th IAEA Technical Meeting on

Recent work on the control of MHD instabilities at

MHD Induced Fast Ion Loss Diagnostic for Alcator C-Mod

First Experiments Testing the Working Hypothesis in HSX:

Influence of energetic ions on neoclassical tearing modes

Stabilization of m/n=1/1 fishbone by ECRH

20th IAEA Fusion Energy Conference,

Ioffe Summary Fast MHD oscillations observed on the TUMAN-3M in absence of energetic ions Bursts of the oscillations correlate with saw-tooth crashes and.

Alfvén eigenmodes (AE) degrade fast-ion confinement in high βN, steady-state scenarios W.W. (Bill) Heidbrink1 with J. Ferron,2 C. Holcomb,3 M. Van Zeeland2,

Presentation transcript:

Fast particle physics on ASDEX Upgrade Sibylle Günter G. Conway1, H.-U. Fahrbach1, C. Forest2, S. daGraca3, M. Garcia Muñoz1 T. Hauff1, J. Hobirk1,V. Igochine1, F. Jenko1, K. Lackner1, P. Lauber1, P. Mc Carthy4, M. Maraschek1, P. Martin5, E. Poli1, K. Sassenberg4, E. Strumberger1, H. Zohm1, ASDEX Upgrade Team Current profile modifications by NBI current drive Interaction of fast ions with MHD instabilities 1 Max-Planck Institut für Plasmaphysik, Garching, Germany, EURATOM Association 2 Dept. of Physics, University of Wisconsin, Madison, Wisconsin, USA 3 Centro de Fusão Nuclear, Associa cão EURATOM/IST, Instituto Superior Técnico, Lisboa, Portugal 4 Physics Department, University College Cork, Cork, Ireland 5 Consorzio RFX, EURATOM-ENEA per la fusione, Padova, Italy

NBI current drive experiments on ASDEX Upgrade Switching experiments between on-and off-axis beams Predicted NBI current profile Adjustment of Te profile (ECRH) on-axis off-axis

Off-axis NBI current drive on ASDEX Upgrade Current profile modification as predicted by TRANSP for moderate heating power: up to 5 MW for high triangularity ( ~0.4) and below for lower triangularity

Strongly reduced current profile modification for larger heating power Agreement with theory only if diffusion of fast particles assumed (Dfast ~ 0.5 m2/s) no effect for on-axis current drive, but off-axis CD strongly affected

Radial profile of loop voltage see P.J. McCarthy et al., TH/P3-7 on-axis phase (stationary) off-axis phase (stationary) beginning of off-axis phase Even in discharges with very small modification of current profile, the loop voltage profile changes as expected immediately after switching from on- to off-axis beams

Local current drive source vanishes within milliseconds Within 100 ms (<< current redistribution time) loop voltage profile becomes flat again! Consistent with redistribution of fast particles

Total current drive efficiency as predicted by theory Loop voltage at plasma edge agrees with TRANSP with and without fast particle redistribution off-axis on-axis Fast particle redistribution: - does not change the total current drive efficiency significantly - needed to explain the off-axis current drive results - would not be measurable for on-axis NBI

Reasons for missing current profile modification? Fast ion redistribution by Alfvén waves? no Alfvén waves observed vb < vA , no difference between experiments with full beam energy (vb > vA /3) and reduced beam energy (vb < vA /3) no dependence on q-profile, monotonic q-profile Current redistribution by MHD? only (1,1) activity observed no influence of qa/q=1 surface (qa varied between 3.9 and 6.2) Fast ion redistribution, correlated to intensity of thermal transport Increase in heating power (independent of radial location and pitch angle reduces CD)

Redistribution of fast ions by background turbulence? usual argument against turbulence affecting fast particles: gyro-averaging of perturbations but additional effect: finite gyro-radii increase correlation length Motion of test particles in (test) turbulent electrostatic field: Full Lorentz dynamics and gyrokinetics

Redistribution of fast ions by background turbulence? Realistic parameters for fusion plasmas: K = 1 … 3 r/lc = 0.2 … 1 significant diffusion of fast ions in background turbulence! Kubo-number: so far simple geometry (drift motion perpendicular to constant magnetic field) and perturbation field, and tracer particles only, but GENE calculations on the way

New diagnostics: Fast particle loss detector energy and pitch angle resolved measurements very high time resolution  phase resolved measurements possible fast particle expulsion by (and in phase with) TAE modes Time [s] n=4 n=5 n=6 .. FILD magnetics

Modulation of NBI source Losses caused by large (2,1) magnetic islands Passing as well as trapped particles expelled in phase with magnetic islands E~100 keV – pitch angle ~35 deg magnetics Inserire grafico piccolo con modulazione NBI (2,1) frequency Modulation of NBI source

Observed losses consistent with modeling (pitch angle, energy, response times) Response of fast particle losses on switch on- and off-experiments Response within microseconds (immdediate losses for particles deposited on HFS, well passing) Response within milliseconds (diffusive losses for particles deposited on LFS) Simulation of particle orbits in 3d equilibrium (Orbit, Gourdon): drift islands orbit stochastization

Losses of trapped particles caused by (3,2) NTMs Fixed phase relation for ICRH heated particles: n=2 symmetry of the particle orbits, fixed phase relation between island and particles possible v||Br0 responsible for outward drift

Discrepancies between calculated and measured TAE damping rates JET: large discrepancies between measured and calculated damping rates for TAE modes (except for PENN model?) too small damping rates from all hybrid MHD- fast particle codes gyrokinetic PENN code: very large radiative damping, strongly dependent on the plasma shape, stable TAE modes in ITER divertor plasmas? New code development: LIGKA fully gyrokinetic (radiative damping) non-perturbative (energetic particle modes) realistic tokamak geometry realistic particle orbits successfully benchmarked

vA= B/ 0 Large damping rates from theory for closed gaps only experimental density profile modified density profile vA= B/ 0 open TAE gap for experimental density profile TAE gap closes modified density profile (within exp. error bars!)

For comparison between theory and experiment measurement of TAE eigenfunction beneficial Perturbtaion amplitude (reflectometry, coh. magnetics) eigenfunction (LIGKA) 0 0.2 0.4 0.6 0.8 1.0 r/a 0.3 0.5 0.7 0.9 r/a Alfvén continuum increase of TAE eigenfunction at plasma edge in gyrokinetic code for closed gap only significant amplitude for measured eigenfunction at the edge = hint for closed gap in ASDEX Upgrade

Summary and Conclusions NBI current drive total NBI current drive efficiency as expected from theory current profile modifications for moderate heating power/strong shaping only proposed reason: turbulent redistribution of fast ions Interaction of fast particles with MHD modes new diagnostics: fast ion loss detector with high time resolution (< 1MHz) fast ion losses in phase with magnetic perturbation, in agreement with modelling TAE damping essentially by closed TAE gaps at the plasma edge

Note: Beam current is particularly susceptible to diffusion Slowing down particles contribute substantially longer to beam current than to energy density or fusion rate 0.01 0.02 0.03 0.2 0.4 0.6 0.8 1 f DD-fusion b jbeam t[s] fractional contribution f of fast particles to DD-fusion, b, and beam current during first t seconds of their slowing down history D-beam, Ebeam=92keV, Te= 1keV, n=5x1019m-3

Are there inconsistencies with other experiments? Slowing down of NBI ions is thought to be classical: TFTR: NBI at r/a=0.5, 2 MW beams with 95 keV, no central heating (nearly no radial diffusion of fast ions: D < 0.05 m2/s), Efthimion IAEA 1988 JET, TFTR: Slowing down of 1 MeV tritons from d(d,p)t : - in low temperature plasmas: classical slowing down - for long slowing down time: D  0.1 m2/s (Conroy EPS 1990, Scott IAEA 1991) DIII-D: anomalous fast ion redistribution needed to match stored energy and neutron rate for NBI heating in TRANSP simulations: D  0.9 m2/s (explanation: Alfvén waves)

Is slowing down of NBI ions always classical? Anomalous fast particle redistribution needed to match the observed neutron rates at DIII-D (John et al., EPS 2001), explained by Alfvén waves Dfast = 0.9 m2/s would stronlgy reduce the beam current drive efficiency

Is slowing down of NBI ions always classical? Challis, Hobirk 2004 Neutron rates for T beam into Ohmic JET discharges: Anomalous fast ion transport for low magnetic field (no influence of MHD modes observed)

NBI current drive system on ASDEX Upgrade 60 keV 93 keV Re-direction of neutral beam injection system strong off-axis deposition by tilt of injection angle significant current drive at half radius expected

New diagnostic on AUG: fast ion loss detector Energy Resolution. Pitch Angle Resolution. perp. energy pitch angle Particles with energies between 5 and 160 keV and pitch angles (V/Vtot) between 0.99 and 0.4

Influence of radiative damping For realistic plasma parameters FLR effects small

Influence of radiative damping Artificial increase of FLR effects: benchmark successful

BUT: Summary NBI current drive NBI current drive can be used to replace inductive current (results consistent with theory, extrapolate well to ITER and DEMO) BUT: So far current profile modifications for very low heating power only On the other hand: Slowing down of NBI ions is thought to be local, usually concluded from : - neutron rates - heat deposition (mostly in low heat flux discharges)