The regular galactic magnetic field and primary cosmic ray energy spectrum at the knee region

The knee in the primary energy spectrum must be sharp enough to reproduce EAS size spectra properly. If the knee is due to the cosmic ray propagation in our Galaxy, so the structure of the regular magnetic field must provide a bump in the knee region. The popular Rand-Kulkarni model does not display such a feature. This paper presents a model of the regular magnetic field which coincides with Rand-Kulkarni's model in the Galactic plane and incorporates a large halo with antysimmetric configuration of the magnetic field thus ensuring a bump.