Generation of zonal flow by electromagnetic fluctuations

The flow generated by electromagnetic drift interchange modes is investigat ed using the reductive perturbative method. In the electrostatic drift case , for which the inverse cascade of energy takes place, flow can provide an absorbing boundary for the long wavelength modes, hence leading to the satu ration of the fluctuations. On the other hand, in the context of the curren t typical tokamaks, the contribution of the electromagnetic part of the flu ctuations to the generation of shear flow is likely to be significant.