Arrival directions of protons of energy 4.0 × 10¹⁹ eV, distributed isotropically over 4π sr at the detector (panel a), are mapped onto the Galactic halo border (panel b), after their back propagation through the large‐scale GMF; 6 × 10³ antiprotons with momentum "−p" are injected isotropically at the Earth. Their positions at the detector are represented by the points in the sky map (panel b), in Galactic coordinates. These points also map the arrival directions of the real protons after their passage through the GMF. A constant B_z component has been included in this simulation. Panel a shows the pointing directions of the same protons at the Galactic halo border, before they are deflected in the GMF. Different shades of gray are used according to the deflection angles of the particles due to the GMF.