Abstract
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 \({}^{2}\) .
