Search for Dark Matter Annihilation in Galaxy Groups

Mariangela Lisanti, Siddharth Mishra-Sharma, Nicholas L. Rodd, Benjamin R. Safdi

Research output: Contribution to journalArticlepeer-review

46 Scopus citations


We use 413 weeks of publicly available Fermi Pass 8 gamma-ray data combined with recently developed galaxy group catalogs to search for evidence of dark matter annihilation in extragalactic halos. In our study, we use luminosity-based mass estimates and mass-to-concentration relations to infer the J factors and associated uncertainties for hundreds of galaxy groups within a redshift range z≲0.03. We employ a conservative substructure boost factor model, which only enhances the sensitivity by an O(1) factor. No significant evidence for dark matter annihilation is found, and we exclude thermal relic cross sections for dark matter masses below ∼30 GeV to 95% confidence in the bb annihilation channel. These bounds are comparable to those from Milky Way dwarf spheroidal satellite galaxies. The results of our analysis increase the tension but do not rule out the dark matter interpretation of the Galactic Center excess. We provide a catalog of the galaxy groups used in this study and their inferred properties, which can be broadly applied to searches for extragalactic dark matter.

Original languageEnglish (US)
Article number101101
JournalPhysical review letters
Issue number10
StatePublished - Mar 9 2018

All Science Journal Classification (ASJC) codes

  • General Physics and Astronomy


Dive into the research topics of 'Search for Dark Matter Annihilation in Galaxy Groups'. Together they form a unique fingerprint.

Cite this