-
Author(s):
S.-I. Itoh, K. Itoh and M. Yagi
-
Title:
A Novel Turbulence Trigger for Neoclassical Tearing Modes in Tokamaks
Date of publication:
July 2003
-
Key words:
neoclassical tearing mode, statistical theory, stochastic excitation, turbulent noise, probability density function, phase boundary, transition rate, nonlinear instability, long time average
-
Abstract:
Stochastic trigger by microturbulence for neoclassical tearing mode (NTM) is studied. NTM induces topological change of magnetic structure and has subcritical nature. Transition rate of, probability density function for and statistically-averaged amplitude of NTM are obtained. Boundary in the phase diagram is determined as the statistical long time average of the transition conditions. NTM can be excited by crossing this boundary even in the absence of other global instabilities.
-
|
