The Latest Results of the Daya Bay Reactor Antineutrino Experiment

The Daya Bay reactor antineutrino experiment was designed to precisely measure the smallest neutrino mixing angle $$\theta_{13}$$ . It has collected $$5.55\times 10^{6}\bar{\nu}_{e}$$ events on distances from 360 to 1900 m between reactors and detectors. Detailed analysis of full data set, 3158 days of operation, gives the world-leading measurement of $$\theta_{13}$$ , $$\sin^{2}2\theta_{13}=0.0851\pm 0.0024$$ . The mass splitting is $$\Delta m_{32}^{2}=(2.466\pm 0.060)\times 10^{{-}3}$$ eV $${}^{2}$$ assuming the normal mass ordering or $$\Delta m_{32}^{2}={-}(2.571\pm 0.060)\times 10^{{-}3}$$ eV $${}^{2}$$ assuming the inverted mass ordering. The results of the search for sterile neutrino show no significant signal. Obtained with CL $${}_{s}$$ method result provides the world’s stringent exclusion of the sterile amplitude $$\sin^{2}2\theta_{14}$$ in a wide range of sterile mass splittings: $$2\times 10^{{-}4}$$ eV $${}^{2}\lesssim\Delta m_{41}^{2}\lesssim 0.3$$ eV $${}^{2}$$ .