2011/06/30 by John Ellis, Keith A. Olive, Vassilis C. Spanos
Physics and Astronomy · #Annihilation #Astrophysics #Cold dark matter #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Fermi Gamma-ray Space Telescope #Galaxy #Geometry #Higgs boson #Higgsino #Minimal Supersymmetric Standard Model #Neutralino #Parameter space #Particle physics #Particle physics theoretical and experimental studies #Physics #Supersymmetry #astro-ph.CO #astro-ph.GA #hep-ph
paper · pdf · doi:10.1088/1475-7516/2011/10/024
33 pages, 12 figures, comments and references added, version to appear in JCAP
arxiv created 2011/10/08 · openalex publication_date 2011/10/18 · arxiv updated 2015/05/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the production of γ rays via LSP annihilations in the core of the Galaxy as a possible experimental signature of the constrained minimal supersymmetric extension of the Standard Model (CMSSM), in which supersymmetry-breaking parameters are assumed to be universal at the GUT scale, assuming also that the LSP is the lightest neutralino χ. The part of the CMSSM parameter space that is compatible with the measured astrophysical density of cold dark matter is known to include a 1 −χ coannihilation strip, a focus-point strip where χ has an enhanced Higgsino component, and a funnel at large tan β where the annihilation rate is enhanced by the poles of nearby heavy MSSM Higgs bosons, A / H . We calculate the total annihilation rates, the fractions of annihilations into different Standard Model final states and the resulting fluxes of γ rays for CMSSM scenarios along these strips. We observe that typical annihilation rates are much smaller in the coannihilation strip for tan β = 10 than along the focus-point strip or for tan β = 55, and that the annihilation branching ratios differ greatly between the different dark matter strips. Whereas the current Fermi-LAT data are not sensitive to any of the CMSSM scenarios studied, and the calculated γ-ray fluxes are probably unobservably low along the coannihilation strip for tan β = 10, we find that substantial portions of the focus-point strips and rapid-annihilation funnel regions could be pressured by several more years of Fermi-LAT data, if understanding of the astrophysical background and/or systematic uncertainties can be improved in parallel.