Can dark matter annihilation dominate the extragalactic gamma-ray background?

Annihilating dark matter (DM) has been discussed as a possible source of gamma-rays from the galactic center (GC) and contributing to the extragalactic gamma-ray background (EGB). Assuming universality of the density profile of DM halos, we show that it is quite unlikely that DM annihilation is a main constituent of EGB, without exceeding the observed gamma-ray flux from the GC. This argument becomes stronger when we include enhancement of the density profiles by supermassive black holes or baryon cooling. The presence of substructure may loosen the constraint, but only if a very large cross section as well as the rather flat profile are realized.

98.70.Rz
98.35.Gi
98.70.Vc
95.35.+d
gamma-ray astronomy
cosmic background radiation
dark matter
dark matter: annihilation
photon: cosmic radiation
cosmic background radiation

References(4)

Figures(0)

TeV gamma-radiation from dark matter annihilation in the Galactic center

Dieter Horns
(
- Heidelberg, Max Planck Inst.
)

- Phys.Lett.B 607 (2005) 225-232,
- Phys.Lett.B 611 (2005) 297 (erratum)
•
e-Print:
- astro-ph/0408192
•
DOI:
- 10.1016/j.physletb.2004.12.057

Supersymmetric dark matter and the extragalactic gamma-ray background

Dominik Elsaesser
(
- Wurzburg U.
)
,
Karl Mannheim
(
- Wurzburg U.
)

- Phys.Rev.Lett. 94 (2005) 171302
•
e-Print:
- astro-ph/0405235
•
DOI:
- 10.1103/PhysRevLett.94.171302

Improving the angular resolution of EGRET and new limits on supersymmetric dark matter near the galactic center

Dan Hooper
(
- Wisconsin U., Madison
)
,
Brenda Dingus
(
- Los Alamos
)

- Adv.Space Res. 35 (2005) 130-134
•
e-Print:
- astro-ph/0212509
•
DOI:
- 10.1016/j.asr.2003.08.053

A Variability and localization study of 3EG J1746-2851

Martin Pohl
(
- Iowa State U.
)

e-Print:
- astro-ph/0412603