Indirect Search for Dark Matter from the center of the Milky Way with the Fermi-Large Area Telescope

Vincenzo Vitale; Aldo Morselli

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arXiv · 0912.3828

Indirect Search for Dark Matter from the center of the Milky Way with the Fermi-Large Area Telescope

Vincenzo Vitale·Aldo Morselli

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Abstract

The Galactic Center region is expected to host the largest density of Dark Matter (DM) particles within the Milky Way. Then a relatively large gamma-ray signal would be expected from the possible DM particles annihilation (or decay). We are searching for the DM gamma-ray signal from the Galactic Center, which is also rich in bright discrete gamma-ray sources. Furthermore intense diffuse gamma-ray emission due to cosmic-ray interactions with interstellar gas and radiation is detected from the same direction. A preliminary analysis of the data, taken during the first 11 months of the Fermi satellite operations, is reported. The diffuse gamma-ray backgrounds and discrete sources, as we know them today, can account for the large majority of the detected gamma-ray emission from the Galactic Center. Nevertheless a residual emission is left, not accounted for by the above models. An improved model of the Galactic diffuse emission and a careful evaluation of new (possibly unresolved) sources (or source populations) will improve the sensitivity for a DM search.

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Vincenzo Vitale, Aldo Morselli. 2009-12-21. Indirect Search for Dark Matter from the center of the Milky Way with the Fermi-Large Area Telescope. https://arxiv.org/abs/0912.3828

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