New Results from RENO

Abstract

RENO (Reactor Experiment for Neutrino Oscillation) is the reactor neutrino experiment which has been taking data from August 2011 with two identical near and far detectors at Hanbit Nuclear Power Plant, Yonggwang, Korea. Using 2,200 days of data, sin 2 2θ 13 and |∆m 2 ee | are precisely measured based on spectral shape of reactor antineutrinos events with delayed neutron captured by Gd : sin 2 2θ 13 = 0.0896 ± 0.0048(stat.) ± 0.0047(syst.) and |∆m 2 ee | = 2.68 ± 0.12(stat.) ± 0.07(syst.)(×10 −3 eV 2 ). Another independent measurement is carried out via antineutrino events with delayed neutron captured by hydrogen based on rate-only information : sin 2 2θ 13 = 0.085 ± 0.008(stat.) ± 0.012(syst.). We also observe a fuel 235 U dependent variation of reactor antineutrino yield with 6.7 σ and 2.6 σ significant hint of the correlation between 5 MeV excess and 235 U fission fraction.