The search for the particle identity of dark matter (DM) continues to be a primary objective in modern physics. In this field, the sub-GeV mass range of DM detection remains a crucial yet challenging window. We investigate synchrotron self-Compton (SSC) emission from electrons and positrons produced by MeV-scale DM annihilation as a novel indirect detection channel. Focusing on the globular cluster Omega Centauri and the sensitivity of the Square Kilometre Array, we derive constraints on the annihilation cross section reaching $⟨\sigma v⟩\sim {10}^{-29}{\mathrm{cm}}^3{\mathrm{s}}^{-1}$ in the tens-of-MeV range. Furthermore, constraints can reach below $⟨\sigma v⟩\sim {10}^{-30}{\mathrm{cm}}^3{\mathrm{s}}^{-1}$ under favorable parameter choices. Although the derived limits depend on the uncertain propagation parameters, the SSC channel remains competitive with existing indirect constraints over a representative range of astrophysical assumptions, establishing SSC emission as a promising probe of sub-GeV DM.

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• Cosmic ray propagation
• Particle dark matter
• Globular clusters