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The cosmic electrons and positrons have been measured with unprecedented statistics up to several hundreds GeV, thus permitting to explore the role that close single sources can have in shaping the flux at different energies. In the present analysis, we consider electrons and positrons in cosmic rays to be produced by spallations of hadron fluxes with the interstellar medium, by a smooth Supernova Remnant (SNR) population, by all the ATNF catalog pulsars, and by few discrete, local SNRs. We test several source models on the e + + e − and e + AMS-02 flux data. For the configurations compatible with the data, we compute the dipole anisotropy in e + + e − , e + , e + /e − from single sources. Our study includes a dedicated analysis to the Vela SNR. We show that Fermi-LAT present data on dipole anisotropy of e + + e − start to explore some of the models for the Vela SNR selected by AMS-02 flux data. We also investigate how the observed anisotropy could result from a combination of local sources. Our analysis shows that the search of anisotropy in the lepton fluxes up to TeV energies can be an interesting tool for the inspection of properties of close SNRs, complementary to the high precision flux data.

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The HAWC Collaboration has discovered a γ-ray emission extended about 2 degrees around the Geminga and Monogem pulsar wind nebulae (PWNe) at γ-ray energies Eγ > 5 TeV. We analyze, for the first time, almost 10 years of γ-ray data obtained with the Fermi Large Area Telescope at Eγ > 8 GeV in the direction of Geminga and Monogem. Since these two pulsars are close the Galactic plane we run our analysis with 10 different interstellar emission models (IEMs) to study the systematics due to the modeling of this component. We detect a γ-ray halo around Geminga with a significance in the range 7.8 − 11.8σ depending on the IEM considered. This measurement is compatible with e + and e − emitted by the PWN, which inverse-Compton scatter (ICS) with photon fields located within a distance of about 100 pc from the pulsar, where the diffusion coefficient is estimated to be around 1.1 × 10 27 cm 2 /s at 100 GeV. We include in our analysis the proper motion of the Geminga pulsar which is relevant for γ rays produced for ICS in the Fermi-LAT energy range. We find that an efficiency of about 1% for the conversion of the spin-down energy of the pulsar into e + and e − is required to be consistent with γ-ray data from Fermi-LAT and HAWC. The inferred contribution of Geminga to the e + flux is at most 20% at the highest energy AMS-02 data. Our results are compatible with the interpretation that the cumulative emission from Galactic pulsars explains the positron excess.PACS numbers: