Experimental study of toroidal Alfvén modes in the Globus-M spherical tokamak
- First Online:
- Cite this article as:
- Petrov, Y.V., Patrov, M.I., Gusev, V.K. et al. Plasma Phys. Rep. (2011) 37: 1001. doi:10.1134/S1063780X11110067
In the experiments carried out on the Globus-M tokamak in regimes with injection of 26-keV neutral beams with a power of 0.75–0.85 MW, two branches of instabilities excited by fast ions were observed in the early stage of a discharge: a low-frequency energetic particle mode (EPM) in the frequency range of 5–30 kHz and a high-frequency mode in the range of 50–200 kHz, identified as a toroidal Alfvén eigenmode (TAE). The TAE developed in the initial phase of the discharge at q(0) > 1 and terminated when sawtooth oscillations were excited at q(0) < 1. The spectrum and spatial localization of the mode agree with predictions of the linear theory. The modes observed in the Globus-M tokamak possess both properties common to other tokamaks and their own specific features.