MAGNETIC HELICITY FLUX AND THE NONLINEAR GALACTIC DYNAMO

摘要

We demonstrate that by including a flux of helicity in the magnetic helicity balance in the nonlinear galactic dynamo equations, the magnetic field dynamics are changed radically. The large-scale magnetic field now saturates at approximately the equipartition level. This is in contrast to the situation without the flux of helicity, when the magnetic helicity is conserved locally, leading to substantially subequipartition values for the equilibrium large-scale magnetic field.