Mimicking diffuse supernova antineutrinos with the Sun as a source

TL;DR

Detecting the cosmic diffuse supernova neutrino background is challenging due to solar antineutrino mimicry at energies below 15 MeV, requiring higher energy detection for unambiguous identification.

Contribution

This paper demonstrates that solar electron antineutrinos can mimic DSNB signals below 15 MeV within current neutrino physics constraints.

Findings

Solar antineutrino flux can imitate DSNB below 15 MeV.

Detection of DSNB requires focusing on energies above 15 MeV.

Spin-flavor oscillations enable solar antineutrino production within known parameters.

Abstract

Measuring the electron antineutrino component of the cosmic diffuse supernova neutrino background (DSNB) is the next ambitious goal for low-energy neutrino astronomy. The largest flux is expected in the lowest accessible energy bin. However, for E < 15 MeV a possible signal can be mimicked by a solar electron antineutrino flux that originates from the usual 8B neutrinos by spin-flavor oscillations. We show that such an interpretation is possible within the allowed range of neutrino electromagnetic transition moments and solar turbulent field strengths and distributions. Therefore, an unambiguous detection of the DSNB requires a significant number of events at E > 15 MeV.