MAGNETIC RECONNECTION AS THE CAUSE OF COSMIC RAY EXCESS FROM THE HELIOSPHERIC TAIL

The observation of a broad excess of sub-TeV cosmic rays compatible with the direction of the heliospheric tail and the discovery of two significant localized excess regions of multi-TeV cosmic rays by the MILAGRO Collaboration, also from the same region of the sky, have raised questions on their origin. In particular, the coincidence of the most significant localized region with the direction of the heliospheric tail and the small angular scale of the observed anisotropy (similar to 10 degrees.) is suggestive of a local origin and of a possible connection to the low-energy broad excess. Cosmic ray acceleration from magnetic reconnection in the magnetotail is proposed as a possible source of the energetic particles.