The effects of vertical outflows on disk dynamos
  We consider the effect of vertical outflows on the mean-field dynamo in a thin disk. These outflows could be due to winds or magnetic buoyancy. We analyse both two-dimensional finite-difference numerical solutions of the axisymmetric dynamo equations and a free-decay mode expansion using the thin-disk approximation. Contrary to expectations, a vertical velocity can enhance dynamo action, provided it is not too strong. In the nonlinear regime this can lead to super-exponential growth of the magnetic field. 
A. Bardou (1), B. v. Rekowski (1), W. Dobler (1), A. Brandenburg (1   and 2), A. Shukurov (1) ((1) Newcastle, UK, (2) NORDIT...