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arXiv · 1908.08884

Constraints on cross-section and lifetime of dark matter with HAWC Observations of dwarf Irregular galaxies

Abstract

It has been shown that the dynamics of dwarf Irregular (dIrr) galaxies are dominated by dark matter. It is also observed that these galaxies have low star formation rates and metallicities, and no gamma-ray emission at ultra very high energies is expected. Because of their distance, dark matter content and vast number, dIrr galaxies are good targets to perform indirect dark matter searches by ground-based and wide field of view gamma-ray experiments, like HAWC. We analyzed data at the position of 31 dIrr galaxies within the HAWC field-of-view and no significant excess was found. Here, we present the individual and combined limits on the annihilation cross-section and decay lifetime of weakly interacting massive particles with a mass between 1 and 100 TeV.

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Sergio Hernández Cadena, José Serna Franco, Rubén Alfaro Molina, Viviana Gammaldi, Ekaterina Karukes, Paolo Salucci. 2019-08-23. Constraints on cross-section and lifetime of dark matter with HAWC Observations of dwarf Irregular galaxies. https://arxiv.org/abs/1908.08884

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