The recent long-term shutdown of Japanese nuclear reactors has resulted in a significantly reduced reactor νe flux at KamLAND. This running condition provides a unique opportunity to confirm and constrain backgrounds for the reactor νe oscillation analysis. The data set also has improved sensitivity for other νe signals, in particular νe's produced in β-decays from 238 U and 232 Th within the Earth's interior, whose energy spectrum overlaps with that of reactor νe's. Including constraints on θ13 from accelerator and short-baseline reactor neutrino experiments, a combined three-flavor analysis of solar and KamLAND data gives fit values for the oscillation parameters of tan 2 θ12 = 0.436

We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7 Be solar neutrinos based on a 165.4 kton-days exposure of KamLAND. The observed rate is 582 ± 94 (kton-days) −1 , which corresponds to a 862 keV 7 Be solar neutrino flux of (3.26 ± 0.52) × 10 9 cm −2 s −1 , assuming a pure electron-flavor flux. Comparing this flux with the standard solar model prediction and further assuming three-flavor mixing, a νe survival probability of 0.66 ± 0.15 is determined from the KamLAND data. Utilizing a global three-flavor oscillation analysis, we obtain a total 7 Be solar neutrino flux of (5.82 ± 1.02) × 10 9 cm −2 s −1 , which is consistent with the standard solar model predictions. PACS numbers: 26.65.+t,14.60.Pq,25.40.Sc * Present address (The same shall apply hereinafter.):

-We search for electron anti-neutrinos (ν e ) from long and short-duration gamma-ray bursts (GRBs) using data taken by the KamLAND detector from August 2002 to June 2013. No statistically significant excess over the background level is found. We place the tightest upper limits on ν e fluence from GRBs below 7 MeV and place first constraints on the relation between ν e luminosity and effective temperature.

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We present a search for the proton decay mode p →νK þ based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from p →νK þ with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is 0.9 AE 0.2 events. The nonbackgroundsubtracted limit on the partial proton lifetime is τ=Bðp →νK þ Þ > 5.4 × 10