Study on the Possible Contribution of Galactic Cosmic Rays to the Galactic Halo Magnetic Field

Based on the measured cosmic ray anisotropy, a model was built to calculate the contribution of the Galactic cosmic ray (GCR) to the large-scale Galactic magnetic field. A general agreement in the large-scale structure of the galactic magnetic field between the calculation and the observation was obtained. This result shows that the Galactic halo magnetic field may partially contributed by the Galactic electric current related to the directional movement of cosmic rays and the model is the correct approach in understanding the possible contribution of cosmic rays to the galactic magnetic field. The model also indicates that the observed anisotropy of cosmic rays on the earth is not a local behavior in the solar vicinity but represents a microcosm of the global anisotropy of GCRs.