SSP2012 - 5th International Symposium on Symmetries in Subatomic Physics

Precise determination of the least well known mixing angle of PMNS matrix, 13, is essential for future measurements of CP-violation in the lepton sector. The Daya Bay reactor neutrino experiment is designed to determine 13 with a sensitivity of 0.01 or better in sin2213.The experiment is located in southern China, near the Daya Bay nuclear power plant. The designed sensitivity is based on comparing the relative flux of antineutrinos between “identical” antineutrino detectors at near and far distances. The detectors are immersed in water pools that provide active and passive shielding against backgrounds. 6 antineutrino detectors are taking data now in 3 experimental halls, the results on the observation of electron antineutrino disappearance at Daya Bay will be shown.