Constraining neutrino-DM interactions with Milky Way dwarf spheroidals and supernova neutrinos

Abstract

We constrain the neutrino-dark matter cross section using properties of the dark matter density profiles of Milky Way dwarf spheroidal galaxies. The constraint arises from core-collapse supernova neutrinos scattering on dark matter as a form of energy injection, allowing the transformation of the dark matter density profile from a cusped profile to a flatter profile. We assume a standard cosmology of dark energy and cold, collisionless, and non-self-interacting dark matter. By requiring that the dark matter cores do not lose too much mass or overshoot constraints from stellar kinematics, we place an upper limit on the cross section of $\sigma_{\nu-\mathrm{DM}}(E_\nu=15 \, \mathrm{MeV}, m_\chi\lesssim130 \, \mathrm{GeV}) \approx 3.4 \times 10^{-23} \, \mathrm{cm^2}$ and $\sigma_{\nu-\mathrm{DM}}(E_\nu=15 \, \mathrm{MeV}, m_\chi\gtrsim130 \, \mathrm{GeV}) \approx 3.2 \times 10^{-27} \left( \frac{m_\chi}{1\,\mathrm{GeV}}\right)^2\, \mathrm{cm^2}$, which is stronger than previous bounds for these energies. Consideration of baryonic feedback or host galaxy effects on the dark matter profile can strengthen this constraint.