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The flux of positrons and electrons ($e^+ + e^-$) has been measured by the $Fermi$ Large Area Telescope (LAT) in the energy range between 7 GeV and 2 TeV. We discuss a number of interpretations of Pass 8 $Fermi$-LAT $e^+ + e^-$ spectrum, combining electron and positron emission from supernova remnants (SNRs) and pulsar wind nebulae (PWNe), or produced by the collision of cosmic rays with the interstellar medium. We find that the $Fermi$-LAT spectrum is compatible with the sum of electrons from a smooth SNR population, positrons from cataloged PWNe, and a secondary component. If we include in our analysis constraints from AMS-02 positron spectrum, we obtain a slightly worse fit to the $e^+ + e^-$ $Fermi$-LAT spectrum, depending on the propagation model. As an additional scenario, we replace the smooth SNR component within 0.7 kpc with the { individual sources} found in Greens catalog of Galactic SNRs. We find that separate consideration of far and near sources helps to reproduce the $e^+ + e^-$ $Fermi$-LAT spectrum. However, we show that the fit degrades when the radio constraints on the positron emission from Vela SNR (which is the main contributor at high energies) are taken into account. We find that a break in the power-law injection spectrum at about 100 GeV can also reproduce the measured $e^+ + e^-$ spectrum} and, among the cosmic-ray propagation models that we consider, no reasonable break of the power-law dependence of the diffusion coefficient can modify the electron flux enough to reproduce the observed shape.
The current version of the Fermi Large Area Telescope data (P8R2) has been publicly available since June 2015, with the caveat that the residual background of all event classes, except ULTRACLEANVETO, was not fully isotropic: it was enhanced by a fac
With 91 months of the publicly available Fermi-LAT Pass 8 data, we analyze the gamma-ray emission from the Milky Way satellites to search for potential line signals due to the annihilation of dark matter particles into double photons. The searched ta
We show the results of analyses performed on high-energy gamma-ray emission during the impulsive phase of solar flares detected by the LAT using Pass 8 data. We compare results obtained with Pass 7 and Pass 8 data sets, using both LAT Low Energy and
The event selection developed for the Fermi Large Area Telescope before launch has been periodically updated to reflect the constantly improving knowledge of the detector and the environment in which it operates. Pass 7, released to the public in Aug
Observations of Gamma-Ray Bursts with the Fermi Large Area Telescope have prompted theoretical advances and posed big challenges in the understanding of such extreme sources, despite the fact that GRB emission above 100 MeV is a fairly rare event. Th