Analysis of the hybrid dissipative trapped electron ITG mode

The effects of dissipative trapped electron on ion temperature gradient-driven instability in sheared slab geometry are considered. Results show that in tokamak plasmas there exists an intrinsic oscillation mode, namely, a hybrid dissipative trapped electron ion temperature gradient mode. When the trapped electron fraction is sufficient high and the trapped electrons are dissipated strongly, the mode is dominated by the trapped electron dynamics and propagates in the electron diamagnetic direction. Numerical evaluation further shows similar results. These conclusions are in agreement with the experimental observations in the latest simulated tokamak experiment on the Columbia Linear Machine.