Results 1 to 10 of about 1,964 (170)
Auroral vortex street formed by the magnetosphere–ionosphere coupling instability [PDF]
Annales Geophysicae, 2015 By performing three-dimensional magnetohydrodynamic simulations including Alfvén eigenmode perturbations most unstable to the ionospheric feedback effects, we examined the auroral vortex street that often appears just before substorm onset.
Y. Hiraki
doaj +1 more source
Excitation of toroidally localized harmonics of global Alfvén eigenmodes
Nuclear Fusion, 2023 The spherical tokamak NSTX and the upgraded, higher toroidal field, NSTX-U, routinely create plasmas with large un-thermalized populations of super-Alfvénic fast ions.
E.D. Fredrickson
doaj +1 more source
Nuclear Fusion, 2023 The aim of this study is to analyze the linear stability of Alfvén eigenmodes (AE) in the QPS device heated by a tangential neutral beam injector (NBI). The analysis is performed using the gyro-fluid code FAR3d, that solves the reduced MHD equations for ...
J. Ortiz +4 more
doaj +1 more source
Eigenmode analysis of ballooning perturbations in the inner magnetosphere of the Earth [PDF]
Annales Geophysicae, 2007 We analyze coupled Alfvén and slow magnetosonic eigenmodes in a dipole geomagnetic field with different ionospheric conductivities in the framework of ideal magnetic hydrodynamics (MHD) with finite pressure.
A. S. Parnowski
doaj +1 more source
The impact of fusion-born alpha particles on runaway electron dynamics in ITER disruptions
Nuclear Fusion, 2023 In the event of a tokamak disruption in a D-T plasma, fusion-born alpha particles take several milliseconds longer to thermalise than the background. As the damping rates drop drastically following the several orders of magnitudes drop of temperature ...
A. Lier +5 more
doaj +1 more source
Elongation effect on beta-induced Alfvén eigenmode
Nuclear Fusion, 2022 Beta induced Alfvén eigenmode (BAE) can be an important candidate for ion loss in burning plasmas. Elongation effect on BAE has been investigated by the gyrokinetic eigenvalue code DAEPS in this work.
Gengxian Li, Yueyan Li, Yong Xiao
doaj +1 more source
High-order coupling of shear and sonic continua in JET plasmas
Nuclear Fusion, 2023 A recent model coupling the shear-Alfvén and acoustic continua, which depends strongly on the equilibrium shaping and on elongation in particular, is employed to explain the properties of Alfvénic activity observed on JET plasmas below but close to the ...
Paulo Rodrigues +10 more
doaj +1 more source
Review of the NPA Diagnostic Application at Globus-M/M2
Atoms, 2023 The application of a neutral particle analyzer (NPA) diagnostic at the Globus-M/M2 spherical tokamaks is discussed. Physical principles of the diagnostic are reviewed. Two general approaches—active and passive measurements—are described.
Nikolai N. Bakharev +2 more
doaj +1 more source
Modelling of energetic particle drive and damping effects on TAEs in AUG experiment with ECCD
Nuclear Fusion, 2023 The impact of electron cyclotron current drive (ECCD)-driven current on toroidicity-induced Alfvén eigenmodes (TAEs) in experiments on the AUG tokamak is investigated numerically. The dynamical evolution of the plasma profiles and equilibria are modelled
R. Calado +17 more
doaj +1 more source
A new paradigm for fast and repetitive chirping of Alfvén eigenmodes
Nuclear Fusion, 2023 A novel 2D nonlinear dynamical paradigm is constructed to interpret the fast and repetitive frequency chirping and amplitude oscillation of Alfvén eigenmodes excited by energetic particles in fusion plasmas as observed in global gyrokinetic simulations ...
Junyi Cheng +6 more
doaj +1 more source