Pumping of magnetic fields by turbulent penetrative convection

A plausible scenario for solar dynamo action is that the large-scale organi zed toroidal magnetic field is generated by the action of strong radial she ar at the base of the solar convection zone, whereas the weaker poloidal fi eld is regenerated by cyclonic convection throughout the convection zone. W e show, using high-resolution three-dimensional numerical simulations, that the required transport of magnetic field from the convection zone to the o vershoot region can be achieved on a convective rather than diffusive times cale by a pumping mechanism in turbulent penetrative compressible convectio n. A layer of magnetic field initially placed in the convection zone is swe pt down by strong sinking plumes, locally amplified, and deposited in the s table region at the base of the convection zone, despite the opposing actio n of magnetic buoyancy. The rate of transport is insensitive to the strengt h of the initial imposed field.