ABSTRACT
This chapter focuses on the calculation of the growth rates of ideal small-scale instabilities of the toroidal plasma. It considers the description of ideal small-scale modes in the inertial region. The structure of the averaged ballooning equation in the inertial region in the toroidal case considered proves the same as in the cylindrical case. The chapter also focuses on the calculation of the growth rates of ballooning modes assuming the plasma to be stable against the Mercier modes. The two different varieties of ballooning modes are distinguished: those far from the Mercier stability boundary and those near this boundary. The first variety is weakly sensitive to the effects responsible for excitation of the Mercier modes, while the second is really a hybrid of the ballooning and the Mercier modes. Such a hybrid has a growth rate increased owing to the effects.
