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Updated: Jun 18, 2026

Setting Limits on Supersymmetry Using Simplified Models

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

Gamma rays from dark matter annihilations strongly constrain the substructure in halos.

Anders Pinzke¹, Christoph Pfrommer, Lars Bergström

¹The Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova University Center, SE - 106 91 Stockholm, Sweden. apinzke@fysik.su.se

Physical Review Letters

|November 13, 2009

Summary

Dark matter (DM) annihilation may produce observable gamma rays from galaxy clusters. This study suggests DM substructures are much more massive than previously thought, similar to warm dark matter.

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Area of Science:

Astrophysics
Particle Physics
Cosmology

Background:

Recent data suggest dark matter (DM) annihilation requires a boosted rate.
This could lead to observable gamma-ray signals from nearby galaxy clusters detectable by the Fermi satellite.

Purpose of the Study:

To investigate the implications of a boosted DM annihilation rate on DM substructure properties.
To constrain the minimum mass of DM substructures using observational data.

Main Methods:

Analysis of EGRET data to establish limits on DM substructure mass.
Numerical simulations of galaxy clusters to accurately model background gamma-ray emissions.
Comparison of gamma-ray emission from DM annihilation and cosmic ray interactions.

Main Results:

The minimum mass of DM substructures is constrained to be approximately 5x10^3 times larger than for cold dark matter.
This mass cutoff is comparable to that expected for warm dark matter.
Without an anomalous boost factor, DM and cosmic ray interactions produce similar levels of gamma-ray emission.

Conclusions:

The findings suggest that DM substructures may be significantly more massive than predicted by standard cold dark matter models.
Future gamma-ray observations hold the potential to differentiate between DM and cosmic ray sources and characterize DM properties.