Dark matter electron anisotropy: A universal upper limit

@article{Borriello2012DarkME,
  title={Dark matter electron anisotropy: A universal upper limit},
  author={Enrico Borriello and Luca Maccione and Alessandro Cuoco},
  journal={Astroparticle Physics},
  year={2012},
  volume={35},
  pages={537-546}
}
We study the dipole anisotropy in the arrival directions of high energy CR electrons and positrons (CRE) of dark matter (DM) origin. We show that this quantity is very weakly model dependent and offers a viable criterion to discriminate among CRE from DM or from local discrete sources, like e.g. pulsars. In particular, we find that the maximum anisotropy which DM can provide is to a very good approximation a universal quantity and, as a consequence, if a larger anisotropy is detected, this… Expand

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References

SHOWING 1-10 OF 90 REFERENCES
Anisotropies in the Diffuse Gamma-Ray Background from Dark Matter with Fermi LAT: a closer look
This thesis addresses the isotropic diffuse gamma-ray background, as measured by the Fermi gamma ray space telescope, and its implications for indirect detection of dark matter. We describe theExpand
Implications of High-Resolution Simulations on Indirect Dark Matter Searches
We study the prospects for detecting the annihilation products of dark matter (DM) in the framework of the two highest-resolution numerical simulations currently available, i.e., Via Lactea II andExpand
High energy positrons from annihilating dark matter
We also consider a range of diffusion parameters consistent with current cosmic ray data. We find that a significant upturn in the positron fraction above 10 GeV is compatible with a wide range ofExpand
New positron spectral features from supersymmetric dark matter: A way to explain the PAMELA data?
Department of Physics, Stockholm University, AlbaNova University Center, SE - 106 91 Stockholm, Sweden(Dated: August 27, 2008)The space-borne antimatter experiment PAMELA has recently reported aExpand
Cosmic ray electron anisotropies as a tool to discriminate between exotic and astrophysical sources
Abstract Recent results from the PAMELA [1] , ATIC [2] , PPB BETS [3] and Fermi [4] collaborations extend the energy range in the e+, e− measurement up to unexplored energies in the hundreds of GeVExpand
The contribution to the antimatter flux from individual dark matter substructures
The local antimatter fluxes induced by an individual dark matter (DM) substructure can be significantly dependent on the proper motion of the source. We derive analytic solutions to the propagationExpand
A theory of dark matter
� > 1GeV 1 . The long range allows a Sommerfeld enhancement to boost the annihilation cross section as required, without altering the weak-scale annihilation cross section during dark matterExpand
Implications of the cosmic ray electron spectrum and anisotropy measured with Fermi-LAT
Abstract The Fermi Large Area Telescope (LAT) collaboration recently released the updated results of the measurement of the cosmic ray electron (CRE) spectrum and published its first constraints onExpand
Cosmic ray electrons and positrons from discrete stochastic sources
The distances that galactic cosmic ray electrons and positrons can travel are severely limited by energy losses to at most a few kiloparsec, thereby rendering the local spectrum very sensitive to theExpand
Profiles of dark haloes: evolution, scatter and environment
We study dark-matter halo density profiles in a high-resolution N-body simulation of aCDM cosmology. Our statistical sample contains �5000 haloes in the range 10 11 10 14 h −1 M⊙ and the resolutionExpand
...
1
2
3
4
5
...