The Dark Matter Diffused Supernova Neutrino Background

TL;DR

This paper introduces the Dark Matter Diffused Supernova Neutrino Background (DMDSNB), a nearly constant flux of scattered supernova neutrinos caused by dark matter interactions, and sets new limits on dark matter-neutrino scattering cross sections using Super-Kamiokande data.

Contribution

It proposes the DMDSNB concept, analyzes its properties, and derives the strongest current bounds on dark matter-neutrino scattering cross sections at MeV energies.

Findings

DMDSNB flux is nearly constant over time.

Sets upper limit on dark matter-neutrino cross section: σ/m < 2.4×10^{-24} cm^2/GeV.

Stronger bounds than previous supernova neutrino attenuation constraints.

Abstract

We consider neutrinos scattering off Milky Way dark matter and the impact of this scattering on supernovae neutrinos. This can take the form of attenuation on the initial flux of neutrinos and a time-delayed flux of scattered neutrinos. Considering dark matter masses above 100 MeV and past Milky Way supernovae, we find this time-delayed flux is nearly constant in time. We call this flux the Dark Matter Diffused Supernova Neutrino Background (DMDSNB), and use Super-K limits on the Diffuse Supernova Neutrino Background (DSNB) flux to set limits on the dark matter-neutrino scattering cross section. We find $\sigma_{\rm DM-\nu}/m_{\rm DM} \lesssim 2.4 \times 10^{-24} \mathrm{cm^2}$/GeV for $m_{\rm DM} \gtrsim 1$ GeV, which is the strongest bound to date on dark matter-neutrino scatterings at MeV energies, and stronger than bounds set from SN1987A neutrino attenuation by an order of magnitude. We end by discussing how the DMDSNB could be distinguished from the DSNB.