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Dark Matter annihilation in Draco: new considerations of the expected gamma flux

M. A. Sanchez-Conde·F. Prada·E. L. Lokas·M. E. Gomez·R. Wojtak·M. Moles
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Abstract

A new revision of the gamma flux that we expect to detect in Imaging Atmospheric Cherenkov Telescopes (IACTs) from neutralino annihilation in the Draco dSph is presented in the context of the minimal supersymmetric standard models (MSSM) compatible with the present phenomenological and cosmological constraints, and using the dark matter (DM) density profiles compatible with the latest observations. This revision takes also into account the important effect of the Point Spread Function (PSF) of the telescope, and is valid not only for Draco but also for any other DM target. We show that this effect is crucial in the way we will observe and interpret a possible signal detection. Finally, we discuss the prospects to detect a possible gamma signal from Draco for current or planned gamma-ray experiments, i.e. MAGIC, GLAST and GAW. Even with the large astrophysical and particle physics uncertainties we find that the chances to detect a neutralino annihilation signal in Draco seem to be very scarce for current experiments. However, the prospects for future IACTs with upgraded performances (especially lower threshold energies and higher sensitivities) such as those offered by the CTA project, might be substantially better.

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M. A. Sanchez-Conde, F. Prada, E. L. Lokas, M. E. Gomez, R. Wojtak, M. Moles. 2007-10-24. Dark Matter annihilation in Draco: new considerations of the expected gamma flux. https://doi.org/10.1103/physrevd.76.123509

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