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Related papers: Global Alfven Eigenmodes in the H-1 heliac

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The aim of the present study is to analyze the effect of the electron cyclotron heating (ECH) on the linear stability of Alfven Eigenmodes (AE) and energetic particle modes (EPM) triggered by energetic ions in Heliotron J plasma. The…

Conditions for net fast ion drive are derived for beam-driven, co-propagating, sub-cyclotron compressional (CAE) and global (GAE) Alfv\'en eigenmodes driven by the Landau resonance with super-Alfv\'enic fast ions. Approximations applicable…

Plasma Physics · Physics 2023-02-10 J. B. Lestz , N. N. Gorelenkov , E. V. Belova , S. X. Tang , N. A. Crocker

This paper presents a dedicated study of plasma-antenna (PA) coupling with the Alfven Eigenmode Active Diagnostic (AEAD) in JET. Stable AEs and their resonant frequencies f, damping rates $\gamma$ < 0, and toroidal mode numbers n are…

Recently-proposed tokamak concepts use magnetic fields up to 12 T, far higher than in conventional devices, to reduce size and cost. Theoretical and computational study of trends in plasma behavior with increasing field strength is critical…

Plasma Physics · Physics 2019-02-19 E. A. Tolman , N. F. Loureiro , P. Rodrigues , J. W. Hughes , E. S. Marmar

In the parts of the solar corona and solar wind that experience the fewest Coulomb collisions, the component proton, electron, and heavy ion populations are not in thermal equilibrium with one another. Observed differences in temperatures,…

Solar and Stellar Astrophysics · Physics 2015-06-05 Steven R. Cranmer , Adriaan A. van Ballegooijen

Toroidal Alfv\'en eigenmodes (TAEs) are gap modes induced by the toroidicity of tokamak plasmas in absence of continuum damping. They can be excited by energetic particles (EPs) when the EP drive exceeds other dampings. A TAE benchmark…

Plasma Physics · Physics 2018-01-17 Yawei Hou , Ping Zhu , Charlson C. Kim , Zhaoqing Hu , Zhihui Zou , Zhengxiong Wang , the NIMROD Team

The aim of this study is to analyze the stability of the Alfven eigenmodes (AE) in the Chinese First Quasi-axisymmetric Stellarator (CFQS). The AE stability is calculated using the code FAR3d that solves the reduced MHD equations to…

Plasma Physics · Physics 2021-04-19 J. Varela , A. Shimizu , D. A. Spong , L. Garcia , Y. Ghai

The nonlinear dynamics of beta-induced Alfv\'en Eigenmodes (BAE) driven by energetic particles (EP) in the presence of ion-temperature-gradient (ITG) turbulence is investigated, by means of selfconsistent global gyrokinetic simulations and…

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

In the presence of energetic particles (EPs) from auxiliary heating and burning plasmas, fishbone instability and Alfv\'en modes can be excited and their transition can take place in certain overlapping regimes. Using the hybrid…

Plasma Physics · Physics 2021-03-19 Zhihui Zou , Ping Zhu , Charlson C. Kim , Xianqu Wang , Yawei Hou

Toroidal Alfven eigenmodes (TAEs) excited in purely ohmically heated plasmas without any auxiliary heating have been identified for the first time in the SUNIST spherical tokamak. The TAE modes are observed during minor disruptions and have…

Plasma Physics · Physics 2016-12-26 Yangqing Liu , Yi Tan , Zhe Gao , Yuhong Xu , Youjun Hu , Song Chai , Yanzheng Jiang , Rui Ke , Heng Zhong , Wenhao Wang

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

In future nuclear fusion reactors, even a small fraction of fusion-born energetic particles (EP) about 100 times hotter than the thermal bulk species, contributes substantially to the kinetic pressure and therefore affect the MHD…

The aim of the study is to analyze the stability of the Energetic Particle Modes (EPM) and Alfven Eigenmodes (AE) in Helitron J and LHD plasma if the electron cyclotron current drive (ECCD) is applied. The analysis is performed using the…

Plasma Physics · Physics 2020-10-09 J. Varela , K. Nagasaki , K. Nagaoka , S. Yamamoto , K. Y. Watanabe , D. A. Spong , L. Garcia , A. Cappa , A. Azegami

The kinetic excitation of ideal magnetohydrodynamic (MHD) discrete Alfven eigenmodes in the second MHD ballooning stable domain is studied in the presence of a thermal ion temperature gradient (ITG), using linear gyrokinetic…

Plasma Physics · Physics 2009-12-08 Andreas Bierwage , Liu Chen , Fulvio Zonca

Helicon plasma sources play a central role in applications ranging from material treatment to space propulsion and fusion, yet the physical processes governing their ignition, transient ionization, and mode evolution remain incompletely…

This work presents the results of a multi mode ITER study on Toroidal Alfven Eigenmodes, using the nonlinear hybrid HAGIS-LIGKA model. It is found that main conclusions from earlier studies of ASDEX Upgrade discharges can be transferred to…

Plasma Physics · Physics 2017-07-11 Mirjam Schneller , Philipp Lauber , Sergio Briguglio

Conditions for net fast ion drive are derived for beam-driven, sub-cyclotron compressional (CAE) and global (GAE) Alfv\'en eigenmodes, such as those routinely observed in spherical tokamaks such as NSTX(-U) and MAST. Both co- and…

Plasma Physics · Physics 2023-02-10 J. B. Lestz , N. N. Gorelenkov , E. V. Belova , S. X. Tang , N. A. Crocker

In ideal MHD, shear Alfv\'{e}n eigenmodes may experience dissipationless damping due to resonant interaction with the shear Alfv\'{e}n continuum. This continuum damping can make a significant contribution to the overall growth/decay rate of…

Plasma Physics · Physics 2015-07-09 G. W. Bowden , M. J. Hole , A. Könies

Linear and nonlinear modelling of Alfv\'enic instabilities, most notably toroidal Alfv\'en eigenmodes (TAEs), obtained by using the global nonlinear electromagnetic gyrokinetic model of the code ORB5 are presented for the 15 MA scenario of…

Plasma Physics · Physics 2020-12-11 T. Hayward-Schneider , Ph. Lauber , A. Bottino , Z. X. Lu