Exploring New Propagation Scales With Galactic Neutrinos

Abstract

The recent observation of high-energy Galactic neutrinos by IceCube allows for searches of new physics affecting neutrino propagation on scales of $O(10^9-10^{15})km/GeV$ in distance over energy. We assess the sensitivity of upcoming measurements of Galactic neutrinos by IceCube and KM3NeT to such new phenomena. We focus on two scenarios: quasi-Dirac neutrinos and neutrino decays. In the quasi-Dirac scenario, we find that joint measurements by IceCube and KM3NeT are sensitive to the mass-squared differences $\delta m^2\in \left(10^{-13.6}\mathrm{e}{\mathrm{V}}^2,10^{-12.3}\mathrm{e}{\mathrm{V}}^2\right)$ at the $90\%$ confidence level. For neutrino decays, the same measurements are sensitive to mass over lifetime ratios $m/\tau >10^{-12.8}\mathrm{e}{\mathrm{V}}^2$ at the same significance. Our results demonstrate that measurements of Galactic neutrinos by a global network of neutrino telescopes can probe signatures of neutrino mass models.

Comments: 16 pages, including 9 figures, 1 table, and 2 appendices. To be submitted to Physical Review D