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تسجيل مستخدم جديدConstraining annihilating dark matter mass by the radio continuum spectral data of NGC4214 galaxy
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Recent gamma-ray and radio observations provide stringent constraints for annihilating dark matter. The current $2sigma$ 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 $5sigma$ 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 $bbar{b}$ 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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