Speaker
Dr
Viktor Bulanin
(St.Petersburg State Polytechnical University)
Description
Owing to the active researches of intermediate regime which is known as limit cycle oscillation (LCO) regime, it is important to investigate oscillations of velocity of zonal flows, plasma density and magnetic field simultaneously. The geodesic acoustic mode (GAM) investigations using multi-diagnostic were carried out on the spherical tokamak Globus-M (R = 0.36 m, a = 0.24 m, Ip = 150 kA, BT = 0.3 T). Variation of GAM intensity showed features of LCO regime. The key implement for researches was a method of Doppler microwave backscattering, or Doppler reflectometry (DR). The diagnostic consisted of two Doppler reflectometers, which were apart in poloidal direction. Oscillations of plasma density at GAM frequencies were investigated using electrostatic probes and detectors of Dα intensity emission, which were detected at different lines of sight. Structure of magnetic field perturbation has been investigated using poloidal and toroidal Mirnov probe arrays. Correlation analysis shown that the structure of ExB velocity oscillations had corresponded to n=0, m=0. The main structure of density fluctuations at GAM frequency had n=0, m=0 mode numbers. Besides the n=0, m=1 component is also presented. The mode structure for magnetic field disturbance was established. To interpret an origin of plasma density global perturbation at GAM frequency plausible model was suggested.
| Country or International Organisation | Russian Federation |
|---|---|
| Paper Number | EX/P1-32 |
Primary author
Dr
Viktor Bulanin
(St.Petersburg State Polytechnical University)
Co-authors
Mrs
A. Iblyaminova
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
A. Petrov
(Saint Petersburg State Polytechnical University, St. Petersburg, Russia)
Mr
A. Yashin
(Saint Petersburg State Polytechnical University, St. Petersburg, Russia)
Prof.
F. Wagner
(Max-Planck-Institut für Plasmaphysik, EURATOM Association, Greifswald, Germany)
Dr
Gleb Kurskiev
(Ioffe Physical-Technical Institute of the Russian Academy of Sciences)
Dr
M. Patrov
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
N. Khromov
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
N. Sakharov
(Ioffe Institute, RAS, St. Petersburg, Russia)
Mr
P. Shchegolev
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
S. Tolstyakov
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
V. Varfolomeev
(Ioffe Institute, RAS, St. Petersburg, Russia)
Dr
Vasily Gusev
(Ioffe Physical-Technical Institute)
Dr
Vladimir Minaev
(Ioffe Institute)
Dr
Yu. Petrov
(Ioffe Institute, RAS, St. Petersburg, Russia)
