Radio continuum and polarization observations of several nearby galaxies allowed to determine their vertical scaleheights, magnetic field strengths and large-scale magnetic field patterns. They all show a similar large-scale magnetic field pattern, which is parallel to the galactic disk along the midplane and X-shaped further away from the disk plane, indepenent of their Hubble type or star formation in the disk or nuclear region. We conclude that - though a high star formation rate (SFR) in the disk increases the total magnetic field strength in the disk and the halo - the SFR does not significantly change the global field configuration nor influence the global scale heights of the radio emission. The observed similar scale heights indicate that star formation regulates the galactic wind velocities. The galactic wind itself may be essential for an effective dynamo action.
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