Particle dark matter scattering on electrons in the Sun may gravitationally capture and self-annihilate inside it to neutrinos and antineutrinos or other final states that in turn decay to them. Using up-to-date Super-Kamiokande measurements of atmospheric electron-type and muon-type neutrinos fluxes, we set the most stringent limits on the electron scattering cross sections for leptophilic dark matter, annihilating to $\nu \overline{\nu }$ and ${\tau }^{+}{\tau }^{-}$ with 100% branching ratio, over mass ranges of $\sim 5–100$ and $\sim 15–100\mathrm{GeV}$, respectively. These limits excludes cross sections down to about ${10}^{-40}–{10}^{-39}{\mathrm{cm}}^2$ which outdo direct searches for dark matter-electron scattering and previously set limits at IceCube. We also derive corresponding reaches at Hyper-K and show that atmospheric neutrino observations restricted to the direction of the Sun can improve sensitivities.

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• Dark matter
• Particle astrophysics
• Particle dark matter