Search for Dark Matter Annihilation in Galaxy Groups

Journal Article · Fri Mar 09 00:00:00 EST 2018 · Physical Review Letters

DOI:https://doi.org/10.1103/physrevlett.120.101101· OSTI ID:1541289

Lisanti, Mariangela ^[1]; Mishra-Sharma, Siddharth ^[1]; Rodd, Nicholas L. ^[2]; Safdi, Benjamin R. ^[3]

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1. Princeton University, NJ (United States)
2. Massachusetts Institute of Technology (MIT), Cambridge, MA (United States)
3. Massachusetts Institute of Technology (MIT), Cambridge, MA (United States); University of Michigan, Ann Arbor, MI (United States)

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. Here we employ a conservative substructure boost factor model, which only enhances the sensitivity by an $$\mathscr{O}$$(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 $$b\bar{b}$$ 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.

• Research Organization: Princeton Univ., NJ (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
• Sponsoring Organization: USDOE Office of Science (SC); Alfred P. Sloan Foundation; Cottrell Scholar Program; National Science Foundation (NSF)
• Grant/Contract Number: SC0007968; SC0013999; SC00012567; PHY-1607611; DESC0007968; DESC00012567; DESC0013999
• OSTI ID: 1541289
• Alternate ID(s): OSTI ID: 1425250
• Report Number(s): MIT/CTP-4931; PUPT- 2534; MCTP 17-15
• Journal Information: Physical Review Letters, Vol. 120, Issue 10; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTRONOMY AND ASTROPHYSICS
cosmology
ark matter
gamma ray astronomy
particle dark matter
galaxy clusters