Features in cosmic-ray lepton data unveil the properties of nearby cosmic accelerators

Abstract

We present a comprehensive discussion about the origin of the features in the leptonic component of the cosmic-ray spectrum. Working in the framework of a up-to-date CR transport scenario tuned on the most recent AMS-02 and Voyager data, we show that the prominent features recently found in the positron and in the all-electron spectra by several experiments are compatible with a scenario in which pulsar wind nebulae (PWNe) are the dominant sources of the positron flux, and nearby supernova remnants (SNRs) shape the high-energy peak of the electron spectrum. In particular we argue that the drop-off in positron spectrum found by AMS-02 at ∼ 300 GeV can be explained—under different assumptions—in terms of a prominent PWN that provides the bulk of the observed positrons in the ∼ 100 GeV domain, on top of the contribution from a large number of older objects. Finally, we turn our attention to the spectral softening at ∼ 1 TeV in the all-lepton spectrum, recently reported by several experiments, showing that it requires the presence of a nearby supernova remnant at its final stage.