作者: Marc Kamionkowski , Shin'ichiro Ando , Samuel K. Lee
DOI: 10.1088/1475-7516/2009/07/007
关键词:
摘要: One of the targets recently launched Fermi Gamma-ray Space Telescope is a diffuse gamma-ray background from dark-matter annihilation or decay in Galactic halo. N-body simulations and theoretical arguments suggest that dark matter halo may be clumped into substructure, rather than smoothly distributed. Here we propose gamma-ray-flux probability distribution function (PDF) as probe substructure We calculate this PDF for phenomenological model determine regions parameter space which distinguished smooth matter. In principle, allows statistical detection even if individual halos cannot detected. It also allow on smallest microhalo mass scales, ~ M_⊕, weakly-interacting massive particles (WIMPs). Furthermore, it provide method to measure function. However, an analysis assumes typical conservative estimate suggests not detectable lifespan specific case WIMP neutralino. Nevertheless, large range annihilation, models, clear signature substructure.