EFFECTS OF ANISOTROPIC ETA(I) AND COLLISIONS ON THE MIXED SLAB AND TOROIDAL ITG MODE

The effects of collisions and anisotropy in the ion temperature gradie nt on the ion-temperature-gradient-driven (ITG) mode are investigated with dissipative trapped electrons and fully kinetic ions, in the pres ence of both transit and magnetic drift resonances. For the slab and t oroidal modes, electron collisions stabilize the ion branch but destab ilize the electron branch. For the mixed slab and toroidal mode, a cou pling effect is found that causes a split of the stability region in t he eta(i parallel-to)-eta(i perpendicular-to) plane. A second stabilit y region at large eta(i perpendicular-to) with electron collisions may provide a possible stabilization scheme for ITG instabilities.