Can we detect antimatter from other galaxies by the use of the Earth's magnetic field and the Moon as an absorber?

Abstract

We propose a search for antimatter in cosmic rays at energies between 1 and 10 TeV. The electric charge values, including their sign, would be determined by a magnetic analysis combined with an energy measurement. We suggest the use of the Earth's magnetic field, which affordsa bending power of ≈ 100 Tesla x metre. The moon would serve as an absorber, removing, from a given angle of observation, the chemical species of a given energy. The detection of the cosmic rays, together with the measurements of their energy and direction, would be made by Cerenkov calorimetry in the atmosphere. Moonlight would be effectively shielded by the ozone layer with detection of UV light in the range from 0.2 to 0.3 μm. No data exist on antimatter cosmic rays beyond ≈ 10 GeV. The proposed method could reach, in the TeV region, a sensitivity of a few 10 −3 on the {antimatter / total} ratio. Present theoretical evaluations of this ratio for baryon-symmetric Universe models are far above such a sensitivity, while the ratio for antiprotons originating from matter-matter interactions within our Galaxy is expected to be much below.