Sensitivity of Neutrino Mass Experiments to the Cosmic Neutrino Background

Abstract

The KATRIN neutrino experiment is a next-generation tritium beta decay experiment aimed at measuring the mass of the electron neutrino to better than 200 meV at 90% C.L. Due to its intense tritium source, KATRIN can also serve as a possible target for the process of neutrino capture, {\nu}e +3H \to 3He+ + e-. The latter process, possessing no energy threshold, is sensitive to the Cosmic Neutrino Background (C{\nu}B). In this paper, we explore the potential sensitivity of the KATRIN experiment to the relic neutrino density. The KATRIN experiment is sensitive to a C{\nu}B over-density ratio of 2.0x 10^9 over standard concordance model predictions (at 90% C.L.), addressing the validity of certain speculative cosmological models.