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Until fairly recently, it was widely accepted that local cosmic ray spectrawere largely featureless power laws, containing limited information on theiracceleration and transport. This viewpoint is currently being revised in thelight of evidence for a variety of spectral breaks in the fluxes of cosmic raynuclei. Here, we focus on cosmic ray electrons and positrons which at thehighest energies must be of local origin due to strong radiative losses. Weconsider a pure diffusion model for their Galactic transport and determine itsfree parameters by fitting data in a wide energy range: measurements of theinterstellar spectrum by Voyager at MeV energies, radio synchrotron data(sensitive to GeV electrons and positrons) and local observations by AMS up to~ 1 TeV. For the first time, we also model the time-dependent fluxes of cosmicray electrons and positrons at GeV energies recently presented by AMS, treatingsolar modulation in a simple extension of the widely used force-fieldapproximation. We are able to reproduce all the available measurements to date.Our model of the interstellar spectrum of cosmic ray electrons and positronsrequires the presence of a number of spectral breaks, both in the sourcespectra and the diffusion coefficients. While we remain agnostic as to theorigin of these spectral breaks, their presence will inform future models ofthe microphysics of cosmic ray acceleration and transport.

Breaks in interstellar spectra of positrons and electrons derived from time-dependent AMS data