Radio and gamma-ray constraints on dark matter annihilation in the Galactic center

Journal Article · Mon Mar 15 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.063516· OSTI ID:21409381

Crocker, R M ^[1]; Bell, N F ^[1]; Balazs, C ^[2]; Jones, D I ^[3]

---

1. School of Physics, University of Melbourne, 3010, Victoria (Australia)
2. School of Physics, Monash University, 3800, Victoria (Australia)
3. Max Planck Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

We determine upper limits on the dark matter (DM) self-annihilation cross section for scenarios in which annihilation leads to the production of electron--positron pairs. In the Galactic center, relativistic electrons and positrons produce a radio flux via synchroton emission, and a gamma-ray flux via bremsstrahlung and inverse Compton scattering. On the basis of archival, interferometric and single-dish radio data, we have determined the radio spectrum of an elliptical region around the Galactic center of extent 3 deg. semimajor axis (along the Galactic plane) and 1 deg. semiminor axis and a second, rectangular region, also centered on the Galactic center, of extent 1.6 deg. x 0.6 deg. The radio spectra of both regions are nonthermal over the range of frequencies for which we have data: 74 MHz-10 GHz. We also consider gamma-ray data covering the same region from the EGRET instrument (about GeV) and from HESS (around TeV). We show how the combination of these data can be used to place robust constraints on DM annihilation scenarios, in a way which is relatively insensitive to assumptions about the magnetic field amplitude in this region. Our results are approximately an order of magnitude more constraining than existing Galactic center radio and gamma-ray limits. For a DM mass of m{sub {chi}=}10 GeV, and an Navarro-Frank-White profile, we find <{sigma}{sub A}v>{<=}fewx10{sup -25} cm{sup 3} s{sup -1}.

• OSTI ID: 21409381
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 6; Other Information: DOI: 10.1103/PhysRevD.81.063516; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
ANNIHILATION
BREMSSTRAHLUNG
COMPTON EFFECT
CROSS SECTIONS
EMISSION
GALAXY NUCLEI
GAMMA RADIATION
GEV RANGE 01-10
GHZ RANGE
MAGNETIC FIELDS
MASS
NONLUMINOUS MATTER
RELATIVISTIC RANGE
SPECTRA
TEV RANGE 01-10
BASIC INTERACTIONS
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
ENERGY RANGE
FREQUENCY RANGE
GEV RANGE
INTERACTIONS
IONIZING RADIATIONS
MATTER
PARTICLE INTERACTIONS
RADIATIONS
SCATTERING
TEV RANGE