Xiao-Yuan Huang, Qiang Yuan, Peng-Fei Yin, Xiao-Jun Bi, Xue-Lei Chen
It was recently reported that there may exist monochromatic $\gamma$-ray emission at $\sim 130$ GeV from the Galactic center in the Fermi Large Area Telescope data, which might be related with dark matter (DM) annihilation. In this work we carry out a comprehensive check of consistency of the results with the DM annihilation scenario, using the Fermi observations of the inner Galaxy, Galactic halo, clusters of galaxies and dwarf galaxies. The possible effects on DM annihilation of substructures based on recent simulations are also taken into account. We find that: 1) the constraints on the annihilation cross section of continuous $\gamma$-ray emission from the Galactic center are as stringent as the "natural" scale assuming thermal freeze-out of DM; 2) the Fermi data of Galactic halo seems to have tension with the DM annihilation interpretation of the $\sim 130$ GeV emission from the inner Galaxy; 3) possible concentration of photons in 120-140 GeV from nearby clusters is revealed; 4) constraints from galaxy cluster (with substructures) are marginally consistent with the DM annihilation scenario to explain the $\sim 130$ GeV emission, and the constraints from dwarf galaxies are weaker.
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http://arxiv.org/abs/1208.0267
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