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Anisotropy of dark matter annihilation with respect to the Galactic plane

Veniamin Berezinsky·Vyacheslav Dokuchaev·Yury Eroshenko
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Abstract

We describe the anisotropy of dark matter clump distribution caused by tidal destruction of clumps in the Galactic disk. A tidal destruction of clumps with orbit planes near the disk plane occurs more efficiently as compared with destruction of clumps at near-polar orbits. A corresponding annihilation of dark matter particles in small-scale clumps produces the anisotropic gamma-ray signal with respect to the Galactic disk. This anisotropy is rather small, 9%, and superimposed on that due to off-centering position of the Sun in the Galaxy. The anisotropy of annihilation signal with respect to the Galactic disk provides a possibility to discriminate dark matter annihilation from the diffuse gamma-ray backgrounds of other origin.

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Veniamin Berezinsky, Vyacheslav Dokuchaev, Yury Eroshenko. 2007-06-28. Anisotropy of dark matter annihilation with respect to the Galactic plane. https://doi.org/10.1088/1475-7516%2F2007%2F07%2F011

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