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Nature Physics 5, 176–177 (1 March 2009) | doi:10.1038/nphys1216

Dark matter: Many birds, one stone

Dan Hooper

An increasingly compelling body of evidence, accumulated over the past months and years, signals that the Milky Way contains a surprising number of highly energetic electrons and positrons. In particular, the satellite-based experiment PAMELA has measured the positron fraction — the ratio of the number of positrons to the number of electrons plus positrons — in the cosmic-ray spectrum to be climbing rapidly above energies of 10 GeV.