Speaker
Description
Additional generations of neutrinos that do not participate in standard V-A interactions - hence called “sterile” - arise in many extensions of the Standard Model. The existence of light sterile neutrino, with masses at eV or sub-eV scale, could explain several anomalies in short neutrino oscillation experiments as well as discrepancy in cosmological measurements of the Hubble parameter. I will report a search for light sterile neutrino mixing in the electron antineutrino disappearance channel by the Daya Bay Reactor Neutrino Experiment in the $2x10^{-4}$ ≲ $|\Delta m^2_{41}|$ ≲ 0.3 eV$^2$ range. The resulting limits on $sin^2 2θ_{14}$ constitute the most stringent constraints to date in the
$|\Delta m^2_{41}|$ ≲ 0.2 eV$^2$ region. A joint analysis with electron antineutrino disappearance measurements from the Daya Bay and Bugey-3 experiments and the measurement of muon (anti)neutrino disappearance by the MINOS experiment will also be presented. The combined results place stringent constraints on electron neutrino and antineutrino appearance driven by sterile neutrino. The sterile-neutrino mixing parameter space allowed by the LSND and MiniBooNE experiments is excluded for $\Delta m^2_{41}$ < 0.8 eV$^2$ at 95% CLs.
