Magnetic field instability driven by anomalous magnetic moments of massive fermions and electroweak interaction with background matter

摘要

It is shown that the electric current of massive fermions along the externalmagnetic field can be excited in the case when particles possess anomalousmagnetic moments and electroweakly interact with background matter. Thiscurrent is calculated on the basis of the exact solution of the Dirac equationin the external fields. It is shown that the magnetic field becomes unstable ifthis current is taken into account in the Maxwell equations. Considering aparticular case of a degenerate electron gas, which can be found in a neutronstar, it is revealed that the seed magnetic field can be significantlyenhanced. The application of the results to astrophysics is also discussed.