| Issue |
EPL
Volume 115, Number 3, August 2016
|
|
|---|---|---|
| Article Number | 35001 | |
| Number of page(s) | 6 | |
| Section | Physics of Gases, Plasmas and Electric Discharges | |
| DOI | https://doi.org/10.1209/0295-5075/115/35001 | |
| Published online | 31 August 2016 | |
Acoustic mode driven by fast electrons in TJ-II Electron Cyclotron Resonance plasmas
Laboratorio Nacional de Fusión, Ciemat - 28040-Madrid, Spain
Received: 9 May 2016
Accepted: 9 August 2016
Intense harmonic oscillations in radiation signals 
are commonly observed during Electron Cyclotron Resonance (ECR) heating in TJ-II stellarator plasmas at low line-averaged electron density, 
. The frequency agrees with acoustic modes. The poloidal modal structure is compatible with Geodesic Acoustic Modes (GAM) but an 
toroidal structure is detected. The modes are found in the proximity of low-order rationals of the rotational transform (
in this work) and are excited by fast-electron populations, but they disappear at the onset of 
-islands rotation.
PACS: 52.35.Fp – Electrostatic waves and oscillations (e.g., ion-acoustic waves) / 52.55.Hc – Stellarators, torsatrons, heliacs, bumpy tori, and other toroidal confinement devices / 52.35.Py – Macroinstabilities (hydromagnetic, e.g., kink, fire-hose, mirror, ballooning, tearing, trapped-particle, flute, Rayleigh-Taylor, etc.)
© EPLA, 2016
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.