Electromagnetic Currents from Electroweak Fermion Level Crossing

Understand

Spectral flow of chiral fermions in the background of electroweak sphalerons is studied.

• A fermion field configuration that interpolates between the sphaleron zero mode and the asymptotic fermion modes is proposed for the level crossing left handed fermion fields.
• It is shown that the fermionic electromagnetic currents with non-trivial helicity are produced during the level crossing.
• Cosmic magnetic field generation due to these currents is briefly discussed.