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Annihilation Radiation from a Dark Matter Spike at the Galactic Centre

Gianfranco Bertone·Guenter Sigl·Joseph Silk
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Abstract

We study annihilation radiation of neutralinos in the Galactic centre, assuming the existence of a 'spike' in the dark matter density profile, due to adiabatic accretion onto the massive black hole lying at the Galactic centre. Under this assumption we find that it is possible to reproduce the observed SgrA* emission at radio and gamma-ray frequencies in a consistent scenario with a magnetic field close to the equipartition strength and with values of $γ$ (the density profile power law index) around 0.1.

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Gianfranco Bertone, Guenter Sigl, Joseph Silk. 2002-09-24. Annihilation Radiation from a Dark Matter Spike at the Galactic Centre. https://doi.org/10.1046/j.1365-8711.2002.05892.x

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