Results 21 to 30 of about 20,493 (125)

Study of fast-ion-driven toroidal Alfvén eigenmodes impacting on the global confinement in TCV L-mode plasmas

Frontiers in Physics, 2023
Following recent observations of unstable Toroidal Alfvén Eigenmodes (TAEs) in a counter-current Neutral Beam Injection (NBI) scenario developed in TCV, an in-depth analysis of the impact of such modes on the global confinement and performance is carried
S. Mazzi, S. Mazzi, M. Vallar, U. Kumar, O. Krutkin, J. Poley-Sanjuan, L. Simons, J. Ball, S. Brunner, S. Coda, J. Garcia, A. Iantchenko, Ye. O. Kazakov, W. H. Lin, J. Ongena, B. Rofman, L. Villard, the TCV team   +17 more
doaj   +1 more source

Measurements of the eigenfunction of reversed shear Alfvén eigenmodes that sweep downward in frequency [PDF]

, 2013
Reversed shear Alfvén eigenmodes (RSAEs) usually sweep upward in frequency when the minimum value of the safety factor qmin decreases in time. On rare occasions, RSAEs sweep downward prior to the upward sweep.
Spong, DA, D. A. Spong, Heidbrink, WW, Austin, ME, M. E. Austin, B. J. Tobias, Tobias, BJ, Van Zeeland, MA, M. A. Van Zeeland, W. W. Heidbrink   +9 more
core   +1 more source

Toroidal Alfvén eigenmodes observed in low power JET deuterium–tritium plasmas

Nuclear Fusion, 2023
The Joint European Torus recently carried out an experimental campaign using a plasma consisting of both deuterium (D) and tritium (T). We observed a high-frequency mode using a reflectometer and an interferometer in a D-T plasma heated with low power ...
H.J.C. Oliver, S.E. Sharapov, Ž. Štancar, M. Fitzgerald, E. Tholerus, B.N. Breizman, M. Dreval, J. Ferreira, A. Figueiredo, J. Garcia, N. Hawkes, D.L. Keeling, P.G. Puglia, P. Rodrigues, R.A. Tinguely, JET Contributors   +15 more
doaj   +1 more source

Comprehensive evaluation of the linear stability of Alfvén eigenmodes driven by alpha particles in an ITER baseline scenario [PDF]

, 2018
The linear stability of Alfvén eigenmodes in the presence of fusion-born alpha particles is thoroughly assessed for two variants of an ITER baseline scenario, which differ significantly in their core and pedestal temperatures. A systematic approach based
Borba, D., Gomes Loureiro, Nuno F, Rodrigues, P., Fazendeiro, L., Polevoi, A.R., Pinches, S.D., Figueiredo, A.C.A., Sharapov, S.E., Nabais, F., Ferreira, J., Coelho, R.   +10 more
core   +1 more source

Nonlinear saturation of reverse shear Alfvén eigenmodes induced by kinetic electrons

Nuclear Fusion, 2022
A strong nonlinear saturation mechanism of the reverse shear Alfvén eigenmode (RSAE) induced by thermal electrons is observed in gyrokinetic ${\delta}f$ particle-in-cell simulation.
Lei Ye, Yang Chen, Guoyong Fu
doaj   +1 more source

The effect of toroidal plasma rotation on low-frequency reversed shear Alfvén eigenmodes in tokamaks [PDF]

, 2012
The influence of toroidal plasma rotation on the existence of reversed shear Alfvén eigenmodes (RSAEs) near their minimum frequency is investigated analytically.
Haverkort, J.W. (Willem)
core   +1 more source

Observation of modes in the sub-cyclotronic range of frequencies in JET

Nuclear Fusion
The excitation of modes in the JET tokamak in the sub-cyclotronic range of frequencies (frequencies comprised between the Alfvén frequency and the cyclotron frequency) is for the first time reported.
F. Nabais, D. Borba, R. Coelho, J. Ferreira, A. Figueiredo, P. Rodrigues, S.E. Sharapov, JET Contributors   +7 more
doaj   +1 more source

Convective Amplification of Ionospheric Feedback by a Finite‐Duration Inertial Alfvén‐Wave Source

Geophysical Research Letters, Volume 53, Issue 20, 28 October 2026.
Abstract We investigate the ionospheric feedback instability (IFI) driven by a finite‐duration localized source of inertial Alfvén waves. Wave‐excited conductance perturbations undergo Pedersen mobility drift in the convection and wave electric fields and are amplified.
R. Rankin, W. Wang, Q.‐G. Zong
wiley   +1 more source

Predictions and Observations of Low-shear Beta-induced Alfvén-acoustic Eigenmodes in Toroidal Plasmas [PDF]

, 2007
New global MHD eigenmode solutions arising in gaps in the low frequency Alfvén -acoustic continuum below the geodesic acoustic mode (GAM) frequency have been found numerically and have been used to explain relatively low frequency experimental signals ...
N.N. Gorelenkov, H.L. Berk, E. Fredrickson, S.E. Sharapov, and JET EFDA Contributors
core  

Kelvin–Helmholtz Spectral Redistribution by Flow and Density Structure at the Dusk Dayside Magnetopause

Journal of Geophysical Research: Space Physics, Volume 131, Issue 10, October 2026.
Abstract We study the development of the Kelvin‐Helmholtz instability (KHI) along the dusk dayside Earth's magnetopause with and without the presence of enhanced plasma density at the shear interface. Using three‐dimensional MAGE global simulations, we establish general KHI growth rate diagrams, which depend sensitively on the transverse profiles of ...
G. Peyrichon, J.‐F. Ripoll, H. El‐Rabii, A. T. Michael, V. G. Merkin, M. Cosmides, K. Sorathia, F. R. Toffoletto, A. Y. Ukhorskiy   +8 more
wiley   +1 more source