Tentative observation of a gamma-ray line at the Fermi LAT

Christoph Weniger

doi:10.1063/1.4772299

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arXiv · 1210.3013

Tentative observation of a gamma-ray line at the Fermi LAT

Christoph Weniger

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Abstract

Using 43 months of public gamma-ray data from the Fermi Large Area Telescope, we find in regions close to the Galactic center at energies of 130 GeV a 4.6 sigma excess that is not inconsistent with a gamma-ray line from dark matter annihilation. When taking into account the look-elsewhere effect, the significance of the observed signature is 3.2 sigma. If interpreted in terms of dark matter particles annihilating into a photon pair, the observations imply a partial annihilation cross-section of about 10^-27 cm^3s^-1 and a dark matter mass around 130 GeV. We review aspects of the statistical analysis and comment on possible instrumental indications.

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Christoph Weniger. 2012-10-10. Tentative observation of a gamma-ray line at the Fermi LAT. https://doi.org/10.1063/1.4772299

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