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

Abstract

Recent gamma-ray and radio observations provide stringent constraints for annihilating dark matter. The current 2σ lower limits of dark matter mass can be constrained to ∼ 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 5σ 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 − , µ + µ − , τ + τ − , W + W − and b b channels respectively. These limits challenge the dark matter interpretation of the gamma-ray, positron and antiproton excess in our Milky Way.