Author/Authors :
Grasso، نويسنده , , D. and Profumo، نويسنده , , S. and Strong، نويسنده , , A.W. and Baldini، نويسنده , , L. and Bellazzini، نويسنده , , R. and Bloom، نويسنده , , E.D. and Bregeon، نويسنده , , J. and Di Bernardo، نويسنده , , G. and Gaggero، نويسنده , , D. and Giglietto، نويسنده , , N. and Kamae، نويسنده , , T. and Latronico، نويسنده , , L. and Longo، نويسنده , , F. and Mazziotta، نويسنده , , M.N. and Moiseev، نويسنده , , A.A. and Morselli، نويسنده , , A. and Ormes، نويسنده , , J.F. and Pesce-Rollins، نويسنده , , M. and Pohl، نويسنده , , M. and Razzano، نويسنده , , M. and Sgro، نويسنده , , C. and Spandre، نويسنده , , G. and Stephens، نويسنده , , T.E.، نويسنده ,
Abstract :
The Fermi-LAT experiment recently reported high precision measurements of the spectrum of cosmic-ray electrons-plus-positrons (CRE) between 20 GeV and 1 TeV. The spectrum shows no prominent spectral features, and is significantly harder than that inferred from several previous experiments. Here we discuss several interpretations of the Fermi results based either on a single large scale Galactic CRE component or by invoking additional electron–positron primary sources, e.g. nearby pulsars or particle dark matter annihilation. We show that while the reported Fermi-LAT data alone can be interpreted in terms of a single component scenario, when combined with other complementary experimental results, specifically the CRE spectrum measured by H.E.S.S. and especially the positron fraction reported by PAMELA between 1 and 100 GeV, that class of models fails to provide a consistent interpretation. Rather, we find that several combinations of parameters, involving both the pulsar and dark matter scenarios, allow a consistent description of those results. We also briefly discuss the possibility of discriminating between the pulsar and dark matter interpretations by looking for a possible anisotropy in the CRE flux.
