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Fifty years after the discovery of antimatter in cosmic rays at the top of the atmosphere, the trend of the most accurate measurements of positrons indicate an excess of these particles above 7 GeV with respect to the secondary component produced by primary cosmic rays propagating in the interstellar medium. This excess is studied here within the scenario of the last 25-year magnetic spectrometer observations. The characteristics of sources contributing to the overall e + flux observed near Earth as a function of particle energy are discussed. Pulsars and magnetars are considered plausible sources of cosmic-ray leptons. The consistency of this possibility is evaluated on the basis of inferred e + source characteristics and parameters set in several other astrophysics fields for these neutron stars. In case all pulsars and magnetars in the vicinity of Earth contribute to e + -e fluxes as expected, a larger positron excess would have been observed. Disks around pulsars and magnetars may play a role in quenching pair production in the magnetosphere of these neutron stars. The magnetar birthrate may also be overestimated.

Cosmic-ray positron measurements: on the origin of the e+ excess and limits on magnetar birthrate