Three-Dimensional Model of Cosmic-Ray Lepton Propagation Reproduces Data from the Alpha Magnetic Spectrometer on the International Space Station
| Autor: | Luca Maccione, Giuseppe Di Bernardo, Dario Grasso, Carmelo Evoli, Daniele Gaggero |
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| Rok vydání: | 2013 |
| Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
Physics 010308 nuclear & particles physics Astrophysics::High Energy Astrophysical Phenomena FOS: Physical sciences General Physics and Astronomy Cosmic ray Electron 01 natural sciences 7. Clean energy Spectral line Nuclear physics Positron 0103 physical sciences Alpha Magnetic Spectrometer Astrophysics - High Energy Astrophysical Phenomena Anisotropy 010303 astronomy & astrophysics Lepton Fermi Gamma-ray Space Telescope |
| Zdroj: | Physical Review Letters. 111 |
| ISSN: | 1079-7114 0031-9007 |
| DOI: | 10.1103/physrevlett.111.021102 |
| Popis: | We study the compatibility of Alpha Magnetic Spectrometer (AMS-02) data on the cosmic-ray (CR) positron fraction with data on the CR electron and positron spectra provided by PAMELA and Fermi LAT. We do that in terms of a novel propagation model in which sources are distributed in spiral arm patterns in agreement with astrophysical observations. While former interpretations assumed an unrealistically steep injection spectrum for astrophysical background electrons, the enhanced energy losses experienced by CR leptons due to the larger average source distance from Earth allow us to reproduce the data with harder injection spectra as expected in a shock acceleration scenario. Moreover, we show that in this approach, and accounting for AMS-02 results, the contribution of nearby accelerators to the fluxes at very high energy can be significantly reduced, thus avoiding any tension with anisotropy upper limits. 4 pages, 5 figures. Accepted for publication in PRL |
| Databáze: | OpenAIRE |
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