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Published on: November 15, 2013
Dark matter interpretation of recent electron and positron data
Lars Bergström1, Joakim Edsjö, Gabrijela Zaharijas
1The Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden.
Physical Review Letters
|August 8, 2009
Summary
An excess of high-energy electrons and positrons detected by Fermi-LAT suggests dark matter. This finding aligns with data from PAMELA and H.E.S.S. experiments, supporting dark matter particle physics models.
Area of Science:
- Astrophysics
- Particle Physics
- Cosmology
Background:
- Analysis of the Fermi-LAT data reveals an unexpected excess in the sum of electrons and positrons.
- This excess is observed in the several hundred GeV energy range.
Purpose of the Study:
- To interpret the observed excess in terms of dark matter models.
- To compare these models with existing data from PAMELA and H.E.S.S.
Main Methods:
- Analysis of Fermi-LAT data on cosmic ray electrons and positrons.
- Comparison with established background models.
- Model fitting using dark matter particle physics scenarios.
- Cross-validation with PAMELA and H.E.S.S. experimental results.
Main Results:
- A significant excess in the electron and positron spectrum was detected, deviating from conventional background models.
- Several dark matter models provide excellent fits to the Fermi-LAT, PAMELA, and H.E.S.S. data.
- The study predicts a potential sharp break in the diffuse gamma-ray spectrum due to final state radiation.
Conclusions:
- The observed cosmic ray excess is consistent with dark matter particle annihilation or decay.
- Dark matter models offer a compelling explanation for the combined astrophysical data.
- Further observations of diffuse gamma-ray emissions may provide additional evidence.
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