Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments
Abstract
Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario.
Significantly improved constraints on the theta(mu e) mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Delta m(41)(2), excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CLs for Delta m(41)(2) < 13 eV(2). Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CLs for Delta m(41)(2) < 1.6 eV(2).