Energy-dependent neutrino mixing parameters at oscillation experiments

Abstract

Neutrino mixing parameters are subject to quantum corrections and hence are scale dependent. This means that the mixing parameters associated with the production and detection of neutrinos need not coincide since these processes are characterized by different energy scales. We show that, in the presence of relatively light new physics, the scale dependence of the mixing parameters can lead to observable consequences in long-baseline neutrino oscillation experiments, such as T2K and $\mathrm{No}\ensuremath{\nu}\mathrm{a}$, and in neutrino telescopes like IceCube. We discuss some of the experimental signatures of this scenario, including zero-baseline flavor transitions, new sources of $CP$-invariance violation, and apparent inconsistencies among measurements of mixing angles at different experiments or oscillation channels. Finally, we present simple, ultraviolet-complete models of neutrino masses, which lead to observable running of the neutrino mixing matrix below the weak scale.