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arXiv · 2009.09562

Constraining annihilating dark matter mass by the radio continuum spectral data of NGC4214 galaxy

Man Ho Chan·Chak Man Lee
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Abstract

Recent gamma-ray and radio observations provide stringent constraints for annihilating dark matter. The current $2\sigma$ lower limits of dark matter mass can be constrained to $\sim 100$ GeV for thermal relic annihilation cross section. In this article, we use the radio continuum spectral data of a nearby galaxy NGC4214 and differentiate the thermal contribution, dark matter annihilation contribution and cosmic-ray contribution. We can get more stringent constraints of dark matter mass and annihilation cross sections. The $5\sigma$ lower limits of thermal relic annihilating dark matter mass obtained are 300 GeV, 220 GeV, 220 GeV, 500 GeV and 600 GeV for $e^+e^-$, $\mu^+\mu^-$, $\tau^+\tau^-$, $W^+W^-$ and $b\bar{b}$ channels respectively. These limits challenge the dark matter interpretation of the gamma-ray, positron and antiproton excess in our Milky Way.

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Man Ho Chan, Chak Man Lee. 2020-09-21. Constraining annihilating dark matter mass by the radio continuum spectral data of NGC4214 galaxy. https://doi.org/10.1103/physrevd.102.063017

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