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Related papers: Experimental Evidence of Nonlinear Avalanche Dynam…

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We present experimental observations suggesting that the non-diffusive avalanche-like events are a prevalent and universal process of the electron turbulent heat transport in tokamak core plasmas. They are observed in the low confinement…

Turbulence in tokamaks generates radially sheared zonal flows. Their oscillatory counterparts, geodesic acoustic modes (GAMs), appear due to the action of the magnetic field curvature. The GAMs can be driven unstable by an anisotropic…

We present test-particle simulations of electrons during a nonlinear MHD simulation of a type-I edge localized mode (ELM) to explore the effect of an eruptive plasma filament on the kinetic level. The electrons are moderately heated and…

Plasma Physics · Physics 2022-11-23 Heinz Isliker , Andres Cathey , Matthias Hoelzl , Stanislas Pamela , Loukas Vlahos

Alfv\'en eigenmodes (AEs) and energetic particle modes (EPMs) are often excited by energetic particles (EPs) in tokamak plasmas. One of the main open questions concerning EP driven instabilities is the non-linear evolution of the mode…

In this work, we present a novel kind of energetic particle modes with frequencies in the range of thermal ion diamagnetic and/or transit frequencies in burning plasmas. It is shown that the continuum structure can be broken by the…

Plasma Physics · Physics 2024-04-09 Yang Li

A reduced 1D model describing the non-linear hybrid LIGKA/HAGIS simulations was developed and successfully tested in [Carlevaro et al. PPCF 64, 035010 (2022)] addressing the ITER 15MA baseline scenario. In this paper, we introduce a…

Plasma Physics · Physics 2024-09-20 Nakia Carlevaro , Matteo V. Falessi , Giovanni Montani , Philipp Lauber

Recent measurements of microwave and X-ray emission during edge localised mode (ELM) activity in tokamak plasmas provide a fresh perspective on ELM physics. It is evident that electron kinetics, which are not incorporated in standard…

Energetic particle redistribution in the presence of multiple Alfv\'en eigenmodes is analyzed in [PPCF 58, 014019 (2016)] for the ITER 15MA baseline scenario: non-linear hybrid simulations (within their well known limits) point out that…

Plasma Physics · Physics 2022-11-17 Nakia Carlevaro , Giovanni Montani , Matteo Valerio Falessi , Philipp Lauber

The confinement of energetic particles (EP) is crucial for an efficient heating of tokamak plasmas. Plasma instabilities such as Alfven Eigenmodes (AE) can redistribute the EP population making the plasma heating less effective, and leading…

Plasma Physics · Physics 2017-04-26 A. Biancalani , A. Bottino , M. Cole , C. Di Troia , Ph. Lauber , A. Mishchenko , B. Scott , F. Zonca

The nonlinear dynamics of energetic particle (EP) driven geodesic acoustic modes (EGAM) in tokamaks is investigated, and compared with the beam-plasma system (BPS). The EGAM is studied with the global gyrokinetic (GK) particle-in-cell code…

Plasma Physics · Physics 2019-01-16 A. Biancalani , N. Carlevaro , A. Bottino , G. Montani , Z. Qiu

We analyze the interaction of a cold fast electron beam with a thermalized plasma, in the presence of many Langmuir modes. The work aims at characterizing the deviation of the system behavior from the single mode approximation, both with…

Plasma Physics · Physics 2016-10-12 Nakia Carlevaro , Giovanni Montani , Davide Terzani

Runaway electrons with strongly anisotropic distributions present in post-disruption tokamak plasmas can destabilize the extraordinary electron (EXEL) wave. The present work investigates the dynamics of the quasi-linear evolution of the…

Plasma Physics · Physics 2015-02-26 G. I. Pokol , A. Kómár , A. Budai , A. Stahl , T. Fülöp

In recent years, a strong reduction of plasma turbulence in the presence of energetic particles has been reported in a number of magnetic confinement experiments and corresponding gyrokinetic simulations. While highly relevant to…

Plasma Physics · Physics 2020-01-08 A. Di Siena , T. Görler , E. Poli , A. Bañón Navarro , A. Biancalani , F. Jenko

Solutions to a model 2D eigenmode equation describing micro-instabilities in tokamak plasmas are presented that demonstrate a sensitivity of the mode structure and stability to plasma profiles. In narrow regions of parameter space, with…

Plasma Physics · Physics 2014-09-05 D. Dickinson , C. M. Roach , J. M. Skipp , H. R. Wilson

The spatio-temporal evolution of the energetic particles in the transport time scale in tokamak plasmas is a key issue of the plasmas confinement, especially in burning plasmas. In order to include sources and sinks and collisional slowing…

Plasma Physics · Physics 2024-05-20 Guo Meng , Philipp Lauber , Zhixin Lu , Andreas Bergmann , Mirelle Schneider

In magnetic confinement fusion devices like tokamaks, it is crucial to confine the high energy fusion-born helium nuclei ($\alpha$-particles) to maintain the energy equilibrium of the plasma. However, energetic ions can excite various…

Plasma Physics · Physics 2015-06-18 László Horváth

A suprathermal population of ions is present in tokamak plasmas due to external heating mechanisms and fusion reactions. These energetic particles (EP) can drive wave unstable, via inverse Landau damping. An example is the…

Plasma Physics · Physics 2026-03-25 R. Wu , A. Biancalani , D. Gossard , R. Ivanov , A. Mishchenko , X. Wang , F. Zonca

The dynamics of long-wavelength ($k_\theta<1.4 \mathrm{\ cm^{-1}}$), broadband (20-200 kHz) electron temperature fluctuations ($\tilde T_e/T_e$) of plasmas in gas-puff experiments were observed for the first time in HL-2A tokamak. In a…

In the full-orbit particle simulations of energetic particle transport in plasmas, the plasma turbulence is typically described as a homogeneous superposition of linear Fourier modes. The turbulence evolution is, however, typically a…

Solar and Stellar Astrophysics · Physics 2012-04-03 Timo Laitinen , Silvia Dalla , James Kelly

The edge plasma turbulence and transport dynamics, as well as the divertor power loads during the thermal quench phase of tokamak disruptions are numerically investigated with BOUT++'s flux-driven, six-field electromagnetic turbulence…

Plasma Physics · Physics 2023-07-26 Ben Zhu , Xue-qiao Xu , Xian-Zhu Tang
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