Constraining new physics scenarios in neutrino oscillations from Daya Bay data

Abstract

We perform for the first time a detailed fit to the $\bar ν_e \to \bar ν_e$ disappearance data of the Daya Bay experiment to constrain the parameter space of models where sterile neutrinos can propagate in a large compactified extra dimension (LED) and models where non-standard interactions affect the neutrino production and detection (NSI). We find that the compactification radius $R$ in LED scenarios can be constrained at the level of $0.57 \, μm$ for normal ordering and of $0.19\, μm$ for inverted ordering, at 2$σ$ confidence level. For the NSI model, reactor data put a strong upper bound on the parameter $\varepsilon_{ee}$ at the level of $\sim 10^{-3}$, whereas the main effect of $\varepsilon_{eμ}$ and $\varepsilon_{eτ}$ is a worsening of the determination of $θ_{13}$.