Euler potentials for a geomagnetic field which includes the Birkeland current

Abstract:

Pairs of Euler potentials, alpha and beta, are known for symmetric configurations, like dipole field (Stern, 1964) or ring current field (Schulz and Chen, 2008), but it is much more difficult to model with this approach a combination of the Earth dipole field and fields generated by the Birkeland and ring currents. In this work we semi-analytically construct Euler potentials for this system and study dynamics of charged particles in the vicinity of field aligned current layers. Results of the calculations can be compared with spacecraft FAC and charged particle observations.