Effects of fluctuation on αΩ dynamo models

We analyse the role of a fluctuating α-effect in αΩ dynamo models, and show that there is a mechanism for magnetic field generation, valid at large-scale separation, deriving from the interaction of mean shear and a fluctuating α-effect. We show that this effect can act as a dynamo even in the absence of a mean α-effect, and that the time-scale for dynamo waves is strongly affected by the presence of fluctuations.