Jamesina J. Simpson

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Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a(More)
B. Aharmim,5 S.N. Ahmed,11 A.E. Anthony,13 E.W. Beier,10 A. Bellerive,3 M. Bergevin,4 S.D. Biller,9 J. Boger,2, a M.G. Boulay,7 M.G. Bowler,9 T.V. Bullard,15 Y.D. Chan,6 M. Chen,11 X. Chen,6, b B.T. Cleveland,9 G.A. Cox,15 C.A. Currat,6 X. Dai,3, 9 F. Dalnoki-Veress,3 H. Deng,10 P.J. Doe,15 R.S. Dosanjh,3 G. Doucas,9 C.A. Duba,15 F.A. Duncan,11 M.(More)
The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is(More)
We have carried out a comprehensive ESR and U-series dating study on the Lake Mungo 3 (LM3) human skeleton. The isotopic Th/U and Pa/U ratios indicate that some minor uranium mobilization may have occurred in the past. Taking such effects into account, the best age estimate for the human skeleton is obtained through the combination of U-series and ESR(More)
This letter reports the initial application of the finitedifference time-domain (FDTD) method to model extremely lowfrequency (ELF) propagation around the entire Earth. Periodic boundary conditions are used in conjunction with a variable-cell two-dimensional TM FDTD grid, which wraps around the complete Earth sphere. The model is verified by numerical(More)
Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to "invisible" modes, such as n-->3nu. The analysis was based on a search for gamma rays from the deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from 16O. A limit of tau(inv)>2 x 10(29) yr is(More)
The Neanderthal hominid Tabun C1, found in Israel by Garrod & Bate, was attributed to either layer B or C of their stratigraphic sequence. We have used gamma-ray spectrometry to determine the 230Th/234U and 231Pa/235U ratios of two bones from this skeleton, the mandible and a femur. The ages calculated from these ratios depend on the uranium uptake history(More)
This paper reports the first application of an optimized geodesic, three-dimensional (3-D) finite-difference time-domain (FDTD) grid to model impulsive, extremely low-frequency (ELF) electromagnetic wave propagation within the entire Earth-ionosphere cavity. This new model, which complements our previously reported efficient 3-D latitude-longitude grid, is(More)
Advances in computing technologies in recent decades have provided a means of generating and performing highly sophisticated computational simulations of electromagnetic phenomena. In particular, just after the turn of the twenty-first century, improvements to computing infrastructures provided for the first time the opportunity to conduct advanced,(More)