Observation of electron-antineutrino disappearance at Daya Bay

par Meng Wang (Shandong University)

jeudi 22 mars 2012, 14:00 → 15:00 Europe/Paris

1222-RC-08 (LPNHE)

The Daya Bay Reactor Neutrino Experiment has measured a non-zero value for the neutrino mixing angle theta13 with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With 55 days of data, 10416 (80376) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R = 0.940 ± 0.011(stat) ± 0.004(syst). A rate-only analysis finds sin2 2θ13 = 0.092 ± 0.016(stat) ± 0.005(syst) in a three-neutrino framework.

Slides wm20120322_paris_dyb.pdf