From 2009, several experiments, like PAMELA, FERMI and AMS, have shown a rise in the fraction of positrons versus electrons+positrons. One of the most probable explanation is due to the presence of nearby sources, like SNRs or pulsars. PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) is a ballooon-borne experiment and is collecting data since 15 June 2006. Its quasi-polar orbit permits to perform a survey in each direction of the sky. The study of the arrival distribution of cosmic ray electrons and positrons from different regions allows the exploration of different origins for the excess.
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