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arXiv · 1908.03712

Fitting dark matter mass with the radio continuum spectral data of the Ophiuchus cluster

Man Ho Chan·Chak Man Lee
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Abstract

Recent gamma-ray and anti-proton analyses suggest that dark matter with mass $m=48-67$ GeV annihilating via $b\bar{b}$ channel can explain the Galactic center GeV gamma-ray excess and the anti-proton excess as measured by AMS-02 simultaneously. In this article, by differentiating the contributions of dark matter annihilation and normal diffuse cosmic rays, we show that dark matter with mass $m=40-50$ GeV annihilating via $b\bar{b}$ channel with the thermal relic annihilation cross section can best explain the radio continuum spectrum of the central radio halo of the Ophiuchus cluster. This mass range, annihilation cross section, and the annihilation channel is completely consistent with the dark matter interpretations of the GeV gamma-ray excess and the anti-proton excess.

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Man Ho Chan, Chak Man Lee. 2019-08-10. Fitting dark matter mass with the radio continuum spectral data of the Ophiuchus cluster. https://arxiv.org/abs/1908.03712

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