On possible interpretations of the high energy electron–positron spectrum measured by the Fermi Large Area Telescope
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- 作者：D. Grasso ; S. Profumo ; A.W. Strong ; L. Baldini ; R. Bellazzini ; E.D. Bloom ; J. Bregeon ; G. Di Bernardo ; D. Gaggero ; N. Giglietto ; T. Kamae ; L. Latronico ; F. Longo ; M.N. Mazziotta ; A.A. Moiseev ; A. Mors
- 关键词：Cosmic ray electrons and positrons ; Pulsars ; Dark-matter ; Fermi-LAT
- 刊名：Astroparticle Physics
- 出版年：2009
- 出版时间：September 2009
- 年：2009
- 卷：32
- 期：2
- 页码：140-151
- 全文大小：1300 K
文摘
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.