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arXiv · 1206.0796

Dark matter line search using a joint analysis of dwarf galaxies with the Fermi Gamma-ray Space Telescope

Alex Geringer-Sameth·Savvas M. Koushiappas
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Abstract

We perform a joint analysis of dwarf galaxy data from the Fermi Gamma-ray Space Telescope in search of dark matter annihilation into a gamma-ray line. We employ a novel statistical method that takes into account the spatial and spectral information of individual photon events from a sample of seven dwarf galaxies. Dwarf galaxies show no evidence of a gamma-ray line between 10 GeV and 1 TeV. The subsequent upper limit on the annihilation cross section to a two-photon final state is 3.9(+7.1)(-3.7) x 10^-26 cm^3/s at 130 GeV, where the errors reflect the systematic uncertainty in the distribution of dark matter within the dwarf galaxies.

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Alex Geringer-Sameth, Savvas M. Koushiappas. 2012-07-19. Dark matter line search using a joint analysis of dwarf galaxies with the Fermi Gamma-ray Space Telescope. https://doi.org/10.1103/physrevd.86.021302

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