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Title: Discriminating different scenarios to account for the cosmic e{sup {+-}} excess by synchrotron and inverse Compton radiation

Journal Article · · Physical Review. D, Particles Fields
;  [1];  [1]; ; ;  [2];  [3]
  1. Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)
  2. Institute of Theoretical Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China)
  3. Department of Physics and Astronomy, University of Glasgow, Kelvin Bldg Rm 620, Glasgow G12 8QQ (United Kingdom)

The excesses of the cosmic positron fraction recently measured by PAMELA and the electron spectra by ATIC, PPB-BETS, Fermi, and H.E.S.S. indicate the existence of primary electron and positron sources. The possible explanations include dark matter annihilation, decay, and astrophysical origin, like pulsars. In this work we show that these three scenarios can all explain the experimental results of the cosmic e{sup {+-}} excess. However, it may be difficult to discriminate these different scenarios by the local measurements of electrons and positrons. We propose possible discriminations among these scenarios through the synchrotron and inverse Compton radiation of the primary electrons/positrons from the region close to the Galactic center. Taking typical configurations, we find the three scenarios predict quite different spectra and skymaps of the synchrotron and inverse Compton radiation, though there are relatively large uncertainties. The most prominent differences come from the energy band 10{sup 4}{approx}10{sup 9} MHz for synchrotron emission and > or approx. 10 GeV for inverse Compton emission. It might be able to discriminate at least the annihilating dark matter scenario from the other two given the high precision synchrotron and diffuse {gamma}-ray skymaps in the future.

OSTI ID:
21316181
Journal Information:
Physical Review. D, Particles Fields, Vol. 80, Issue 2; Other Information: DOI: 10.1103/PhysRevD.80.023007; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
Country of Publication:
United States
Language:
English