Experimental Observation of Magnetic Island Heteroclinic Bifurcation in Tokamaks

Bardóczi, L.; Evans, T. E.

doi:10.1103/physrevlett.126.085003

Experimental Observation of Magnetic Island Heteroclinic Bifurcation in Tokamaks

Journal Article · Fri Feb 26 00:00:00 EST 2021 · Physical Review Letters

DOI:https://doi.org/10.1103/physrevlett.126.085003· OSTI ID:1768245

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General Atomics, San Diego, CA (United States); General Atomics, Energy & Advanced Concepts, DIII-D
General Atomics, San Diego, CA (United States)

We report empirical observations of magnetic island heteroclinic bifurcation for the first time. This behavior is observed in interacting coupled 2/1 tearing modes in the core of a DIII-D tokamak plasma. Poincaré maps constrained by measured magnetic amplitudes and phasing show bifurcation from heteroclinic to homoclinic topology in the 2/1 island as the 4/2 relative amplitude (R_4/2) decreases. Initially, the local electron temperature peak in the 2/1 island splits, consistent with two O points. As R_4/2 decreases a single peak forms, consistent with one O point. Lastly, these call for developing tearing stability theory and control solutions for heteroclinic islands in tokamaks.

View Accepted Manuscript (DOE)

Research Organization:: General Atomics, San Diego, CA (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Grant/Contract Number:: FC02-04ER54698; SC0018030

OSTI ID:: 1768245

Journal Information:: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 8 Vol. 126; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

References (19)

Polarimetry of motional Stark effect and determination of current profiles in DIII‐D (invited) Wróblewski, D.; Lao, L. L. Review of Scientific Instruments, Vol. 63, Issue 10 https://doi.org/10.1063/1.1143463	journal	October 1992
Design and operation of the multipulse Thomson scattering diagnostic on DIII‐D (invited) Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C. Review of Scientific Instruments, Vol. 63, Issue 10 https://doi.org/10.1063/1.1143545	journal	October 1992
Control of neoclassical tearing modes in DIII–D La Haye, R. J.; Günter, S.; Humphreys, D. A. Physics of Plasmas, Vol. 9, Issue 5 https://doi.org/10.1063/1.1456066	journal	May 2002
Electron cyclotron emission radiometer upgrade on the DIII-D tokamak Austin, M. E.; Lohr, J. Review of Scientific Instruments, Vol. 74, Issue 3 https://doi.org/10.1063/1.1530387	journal	March 2003
Magnetic diagnostic system of the DIII-D tokamak Strait, E. J. Review of Scientific Instruments, Vol. 77, Issue 2 https://doi.org/10.1063/1.2166493	journal	February 2006
An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements King, J. D.; Strait, E. J.; Boivin, R. L. Review of Scientific Instruments, Vol. 85, Issue 8 https://doi.org/10.1063/1.4891817	journal	August 2014
Non-perturbative measurement of cross-field thermal diffusivity reduction at the O-point of 2/1 neoclassical tearing mode islands in the DIII-D tokamak Bardóczi, L.; Rhodes, T. L.; Carter, T. A. Physics of Plasmas, Vol. 23, Issue 5 https://doi.org/10.1063/1.4948560	journal	May 2016
Shrinking of core neoclassical tearing mode magnetic islands due to edge localized modes and the role of ion-scale turbulence in island recovery in DIII-D Bardóczi, L.; Rhodes, T. L.; Carter, T. A. Physics of Plasmas, Vol. 24, Issue 6 https://doi.org/10.1063/1.4985078	journal	June 2017
Hamiltonian guiding center drift orbit calculation for plasmas of arbitrary cross section White, R. B.; Chance, M. S. Physics of Fluids, Vol. 27, Issue 10 https://doi.org/10.1063/1.864527	journal	January 1984
Helical temperature perturbations associated with tearing modes in tokamak plasmas Fitzpatrick, Richard Physics of Plasmas, Vol. 2, Issue 3 https://doi.org/10.1063/1.871434	journal	March 1995
Equilibrium analysis of current profiles in tokamaks Lao, L. L.; Ferron, J. R.; Groebner, R. J. Nuclear Fusion, Vol. 30, Issue 6 https://doi.org/10.1088/0029-5515/30/6/006	journal	June 1990
Quantitative modeling of neoclassical tearing mode driven fast ion transport in integrated TRANSP simulations Bardóczi, L.; Podestà, M.; Heidbrink, W. W. Plasma Physics and Controlled Fusion, Vol. 61, Issue 5 https://doi.org/10.1088/1361-6587/ab0f08	journal	April 2019
Topological bifurcation of magnetic islands in NSTX-U Wu, W.; Evans, T. E.; Canal, G. P. Nuclear Fusion, Vol. 59, Issue 6 https://doi.org/10.1088/1741-4326/ab127e	journal	April 2019
Heteroclinic Structure of Parametric Resonance in the Nonlinear Schrödinger Equation Conforti, M.; Mussot, A.; Kudlinski, A. Physical Review Letters, Vol. 117, Issue 1 https://doi.org/10.1103/PhysRevLett.117.013901	journal	June 2016
Topological and metric analysis of heteroclinic crisis in laser chaos Finardi, M.; Flepp, L.; Parisi, J. Physical Review Letters, Vol. 68, Issue 20 https://doi.org/10.1103/PhysRevLett.68.2989	journal	May 1992
Identification of Intermittent Ordered Patterns as Heteroclinic Connections Stone, E.; Gorman, M.; el-Hamdi, M. Physical Review Letters, Vol. 76, Issue 12 https://doi.org/10.1103/PhysRevLett.76.2061	journal	March 1996
Dynamical Encoding by Networks of Competing Neuron Groups: Winnerless Competition Rabinovich, M.; Volkovskii, A.; Lecanda, P. Physical Review Letters, Vol. 87, Issue 6 https://doi.org/10.1103/PhysRevLett.87.068102	journal	July 2001
Heteroclinic Synchronization: Ultrasubharmonic Locking Rabinovich, Mikhail I.; Huerta, Ramón; Varona, Pablo Physical Review Letters, Vol. 96, Issue 1 https://doi.org/10.1103/PhysRevLett.96.014101	journal	January 2006
Heteroclinic chaos in a Josephson-junction system perturbed by dichotomous noise excitation Lei, Youming; Fu, Rui EPL (Europhysics Letters), Vol. 112, Issue 6 https://doi.org/10.1209/0295-5075/112/60005	journal	December 2015

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