Effects of anisotropic ηi and collisions on the mixed slab and toroidal ITG mode

The effects of collisions and anisotropy in the ion temperature gradient on the ion-temperature-gradient-driven (ITG) mode are investigated with dissipative trapped electrons and fully kinetic ions, in the presence of both transit and magnetic drift resonances. For the slab and toroidal modes, electron collisions stabilize the ion branch but destabilize the electron branch. For the mixed slab and toroidal mode, a coupling effect is found that causes a split of the stability region in the ηiparallel-ηiperpendicular plane. A second stability region at large ηiperpendicular with electron collisions may provide a possible stabilization scheme for ITG instabilities