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arXiv · 1312.3945

Combined Flux and Anisotropy Searches Improve Sensitivity to Gamma Rays from Dark Matter

Sheldon S. Campbell·John F. Beacom
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Abstract

Searches for dark matter annihilation signals in the diffuse gamma-ray background are promising. We present the first comprehensive study utilizing both flux and anisotropy, using the example of a spectral line signal. Besides improving sensitivity, a combined analysis will help separately determine the particle properties of dark matter and the cosmological aspects of its clumping into halo substructure. The significance of a signal in a shot-noise-dominated anisotropy analysis increases linearly with time $t$, as opposed to $\sqrt{t}$ for a flux analysis, so a flux hint might be confirmed with an anisotropy signal. A first combined line search with Fermi-LAT would provide powerful new sensitivity; one with the proposed GAMMA-400 would be dramatically better.

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Sheldon S. Campbell, John F. Beacom. 2013-12-13. Combined Flux and Anisotropy Searches Improve Sensitivity to Gamma Rays from Dark Matter. https://arxiv.org/abs/1312.3945

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