The Plutonium Management and Disposition Agreement between the United States and Russia makes arrangements for the disposal of 34 metric tons of excess weapon-grade plutonium. Under this agreement Russia plans to dispose of its excess stocks by processing the plutonium into fuel for fast breeder reactors. To meet the disposition requirements this fuel would be burned while the fast reactors are run as burners, i.e., without a natural uranium blanket that can be used to breed plutonium surrounding the core. This article discusses the potential application of antineutrino monitoring to the verification of the presence of a breeding blanket. It is found that a 36 kg antineutrino detector, exploiting coherent elastic neutrino-nucleus scattering and made of silicon could determine the presence of a breeding blanket at a liquid sodium cooled fast reactor at the 95 percent confidence level within 90 days.

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The ILL experiment, one of the "reactor anomaly" experiments, is re-examined. ILL's baseline of 8.78 m is the shortest of the reactor anomaly short baseline experiments, and it is the experiment that finds the largest fraction of the electron antineutrinos disappearing -about 20%. Previous analyses, if they do not ignore the ILL experiment, use functional forms for chisquare which are either totally new and unjustified, are the magnitude chisquare (also termed a "rate analysis"), or utilize a spectral form for chisquare which double counts the systematic error. We do an analysis which utilizes the standard, conventional form for chisquare as well as a derived functional form for a spectral chisquare. We find that when analyzed with a conventional chisquare that includes spectral information or with a spectral chisquare that is independent of the magnitude of the flux, the results are a set of specific values for possible mass-squared differences of the fourth neutrino and where the minimum chisquare difference values are significantly enhanced over previous analyses of the ILL experiment. For the Huber flux and the conventional chisquare, the two most preferred values are mass-squared differences of 0.90 and 2.36 eV 2 preferred at ∆χ 2 min values of -12.1 and -13.0 (3.5 and 3.6 σ), respectively. For the Daya Bay flux and conventional chisquare we find 0.95 and 2.36 eV 2 preferred at ∆χ 2 min of -8.22 and -9.45 (2.9 and 3.1 σ), respectively. For the spectral chisquare and either flux these values are 0.95 and 2.36 eV 2 preferred at ∆χ 2 min of -10.5 and -11.7(3.2 and 3.4 σ), respectively. These are to be compared to -4.4 (2.1 σ) found in the original reactor anomaly anaysis for all of the experiments excepting the ILL experiment.

The Daya Bay, RENO, and Double Chooz experiments have discovered a large non-zero value for θ13. We present a global analysis that includes these three experiments, Chooz, the Super-K atmospheric data, and the νµ → νe T2K and MINOS experiments that are sensitive to the hierarchy and the sign of θ13. We report preliminary results in which we fix the mixing parameters other than θ13 to those from a recent global analysis. Given there is no evidence for a non-zero CP violation, we assume δ = 0. T2K and MINOS lie in a region of L/E where there is a hierarchy degeneracy in the limit of θ13 → 0 and no matter interaction. For nonzero θ13, the symmetry is partially broken, but a degeneracy under the simultaneous exchange of both hierarchy and the sign of θ13 remains. Matter effects break this symmetry such that the positions of the peaks in the oscillation probabilities maintain the two-fold symmetry, while the magnitude of the oscillations is sensitive to the hierarchy. This renders T2K and NOνA, with different baselines and different matter effects, better able in combination to distinguish the hierarchy and the sign of θ13. The present T2K and MINOS data do not distinguish between hierarchies or the sign of θ13, but the large value of θ13 yields effects from atmospheric data that do. We find for normal hierarchy, positive θ13, sin 2 2θ13 = 0.090 ± 0.020 and is 0.2% probable it is the correct combination; for normal hierarchy, negative θ13, sin 2 2θ13 = 0.108 ± 0.023 and is 2.2% probable; for inverse hierarchy, positive θ13, sin 2 2θ13 = 0.110±0.022 and is 7.1% probable; for inverse hierarchy, negative θ13, sin 2 2θ13 = 0.113 ± 0.022 and is 90.5% probable, results that are inconsistent with two similar analyses.