Probing light sterile neutrinos in medium baseline reactor experiments

TL;DR

This paper investigates the potential existence of light sterile neutrinos using data from medium baseline reactor experiments, finding moderate improvements in data fit and confirming the robustness of theta_13 measurements despite sterile neutrino presence.

Contribution

It provides the first combined analysis of Double Chooz, Daya Bay, and RENO data to constrain sterile neutrino mixing parameters in the (10^{-3}-10^{-1}) eV^2 mass squared difference range.

Findings

Existence of a light sterile neutrino slightly improves data fit.

Measured theta_13 remains reliable even with sterile neutrinos.

Sterile neutrino mixing angle sin^2 2 theta_{14} < 0.1 at 95% C.L.

Abstract

Medium baseline reactor experiments (Double Chooz, Daya Bay and RENO) provide a unique opportunity to test the presence of light sterile neutrinos. We analyze the data of these experiments in the search of sterile neutrinos and also test the robustness of theta_13 determination in the presence of sterile neutrinos. We show that existence of a light sterile neutrino state improves the fit to these data moderately. We also show that the measured value of theta_{13} by these experiments is reliable even in the presence of sterile neutrinos, and the reliability owes significantly to the Daya Bay and RENO data. From the combined analysis of the data of these experiments we constrain the mixing of a sterile neutrino with mass squared difference in the range of (10^{-3}-10^{-1}) eV^2 to sin^2 2 theta_{14} <0.1 at 95 % C.L..