Effects of a sheared ion velocity on the linear stability of ITG modes

Abstract

The linear dispersion of the ion temperature gradient (ITG) modes, in the presence of a non uniform background ion velocity U || = U || (x) e z , in the direction of the sheared equilibrium magnetic field B 0 = B 0 (x) e z , has been studied in the frame of the two-fluid guiding center approximation, in slab geometry. Generally speaking, the presence of an ion flow destabilizes the oscillations. The role of the excited K-H instability is discussed.