Abstract
Toroidal Alfven eigenmodes (TAE) and ellipticity induced Alfven eigenmodes (EAE) driven by fast electrons are observed for the first time in steady-state EAST plasmas heated by lower hybrid wave (LHW). For the analyzed discharge four modes appear after the injection of LHW. Comparing experimental observations with simulation, high frequency modes are located near r/a ≈ 0.1-0.4 and low frequency mode is near r/a ≈ 0.6-0.8. The two positions are very close to where most of the heating power is deposited and population inversion occurs. Analysis of resonance condition between particles and waves indicates that barelypassing, deeply trapped and barely-trapped electrons can drive the mode.
| Original language | English |
|---|---|
| Article number | 096032 |
| Journal | Nuclear Fusion |
| Volume | 58 |
| Issue number | 9 |
| DOIs | |
| State | Published - Jul 17 2018 |
Funding
The authors wish to thank Dr. Youwen Sun and Dr Wei Chen for helping us understanding the physical picture of wave-particle interaction. The authors also want to thank Dr Ran Chen and Dr Qingquan Yang for valuable discussion of the EAST experiments. Finally, the authors would like to express gratitude to Dr Mike Van Zeeland for his constructive advice of organizing the work. The work is supported by the National Natural Science Fundation of China under grant nos. 11575245 and Hefei Science Center CAS (2017HSC-IU004).
| Funders | Funder number |
|---|---|
| Hefei Science Center CAS | 2017HSC-IU004 |
| National Natural Science Fundation of China | 11575245 |
Keywords
- Alfven eigenmodes
- energetic electrons
- lower hybrid wave
