Gamma-rays from Nearby Clusters: Constraints on Selected Decaying Dark Matter Models
arXiv:1101.5878 · doi:10.1016/j.physletb.2011.02.055
Abstract
Recently, the Fermi-LAT collaboration reported upper limits on the GeV gamma-ray flux from nearby clusters of galaxies. Motivated by these limits, we study corresponding constraints on gamma-ray emissions from two specific decaying dark matter models, one via grand unification scale suppressed operators and the other via R-parity violating operators. Both can account for the PAMELA and Fermi-LAT excesses of e^\pm. For GUT decaying dark matter, the gamma-rays from the M49 and Fornax clusters, with energy in the range of 1 to 10 GeV, lead to the most stringent constraints to date. As a result, this dark matter is disfavored with conventional model of e^\pm background. In addition, it is likely that some tension exists between the Fermi-LAT e^\pm excess and the gamma ray constraints for any decaying dark matter model, provided conventional model of e^\pm background is adopted. Nevertheless, the GUT decaying dark matter can still solely account for the PAMELA positron fraction excess without violating the gamma-ray constraints. For the gravitino dark matter model with R-parity violation, cluster observations do not give tight constraints. This is because a different e^\pm background has been adopted which leads to relatively light dark matter mass around 200 GeV.
17 pages, 4 figures, version to appear in Phys. Lett. B
References in corpus (14)
- PYTHIA 6.4 Physics and Manual
- Observation of an anomalous positron abundance in the cosmic radiation
- Measurement of the Cosmic Ray e+ plus e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope
- Decaying Dark Matter can explain the electron/positron excesses
- Gamma-ray and radio tests of the e+e- excess from DM annihilations
- Inverse Compton constraints on the Dark Matter e+e- excesses
- High Energy Cosmic Rays from the Decay of Gravitino Dark Matter
- Decaying Dark Matter as a Probe of Unification and TeV Spectroscopy
- High-energy Cosmic-Ray Positrons from Hidden-Gauge-Boson Dark Matter
- Gamma Rays from Clusters and Groups of Galaxies: Cosmic Rays versus Dark Matter
- R-violating Decay of Wino Dark Matter and electron/positron Excesses in the PAMELA/Fermi Experiments
- Probing Gravitino Dark Matter with PAMELA and Fermi
- Universally Leptophilic Dark Matter From Non-Abelian Discrete Symmetry
- Decaying Dark Matter in Supersymmetric Model and Cosmic-Ray Observations