Neutrino fog for dark matter-electron scattering experiments

Abstract

The search for sub-GeV dark matter via scattering on electrons has ramped up in the last few years. Like in the case of dark matter scattering on nuclei, electron-recoil-based searches also face an ultimate background in the form of neutrinos. The so-called “neutrino fog” refers to the range of open dark matter parameter space where the background of neutrinos can potentially prevent a conclusive discovery claim of a dark matter signal from being made. In this study, we map the neutrino fog for a range of electron recoil experiments based on silicon, germanium, xenon, and argon targets. In analogy to the nuclear recoil case, we also calculate the “edge” to the neutrino fog, which can be used as a visual guide to determine where neutrinos become an important background—this boundary excludes some parts of the key theory milestones used to motivate these experiments. Published by the American Physical Society 2024