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We have extended our study of the competition between the drive andstabilization of plasma microinstabilities by sheared flow to includeelectromagnetic effects at low plasma $\beta$ (the ratio of plasma to magneticpressure). The extended system of characteristic equations is formulated, for adissipative fluid model developed from the gyrokinetic equation, using atwisting mode representation in sheared slab geometry and focusing on the iontemperature gradient mode. Perpendicular flow shear convects perturbationsalong the field at the speed we denote as $Mc_s$ (where $c_s$ is the soundspeed). $M > 1/ \sqrt{\beta}$ is required to make the system characteristicsunidirectional and inhibit eigenmode formation, leaving only transitoryperturbations in the system. This typically represents a much larger flow shearthan in the electrostatic case, which only needs $M>1$. Numerical investigationof the region $M < 1/\sqrt{\beta}$ shows the driving terms can conflict, as inthe electrostatic case, giving low growth rates over a range of parameters.Also, at modest drive strengths and low $\beta$ values typical of experiments,including electromagnetic effects does not significantly alter the growthrates. For stronger flow shear and higher $\beta$, geometry characteristic ofthe spherical tokamak mitigates the effect of an instability of the shearAlfv\'{e}n wave, driven by the parallel flow shear.

Electromagnetic effects in the stabilization of turbulence by sheared flow