[en] The low energy (<200 MeV) atmospheric neutrino flux is calculated by a three-dimensional Monte Carlo cascade in order to estimate the backgrounds for low energy astrophysical neutrino detections. The author finds that the atmospheric neutrino flux is a significant background and allows only a narrow neutrino astronomy window at 14-30 MeV for the continuous flux of neutrinos from relic supernova explosions. The calculations includes the geomagnetic latitude dependence of detector site and the angular dependence of neutrino detection direction as an extension to the one-dimensional calculation for use in future neutrino oscillation experiments with atmospheric neutrinos. The atmospheric muon flux calculation, a by-product of this three-dimensional atmospheric neutrino calculation, agrees with the measurement at sea-level within 10% accuracy. The author also calculates the medium energy (300 MeV ≤ E/sub nu/ ≤ 3 GeV) atmospheric neutrino flux by a one-dimensional Monte Carlo cascade in order to find the backgrounds for underground nucleon decay experiments and for neutrino oscillation tests with atmospheric neutrinos. Experiments at different latitudes have already confirmed both the atmospheric neutrino fluxes to about 20% accuracy and the gross features of the neutrino angular distribution. As well, the authors calculate the ultra-high energy (>1 TeV) astrophysical neutrino flux by a nearly model-independent analytic method for estimate the ultra-high energy neutrino flux from active astrophysical compact objects by comparison with the observed gamma ray flux at comparable energies. Applied to several known gamma ray sources, the calculation shows the neutrino flux from them to be only marginally detectable by DUMAND-size underwater detectors

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[en] It is shown that ¹/₂₄th scale model test results accurately predict the flow-induced vibration and modes of full-size reactor internals. Dimensional analysis principles are reviewed and the similitude requirements for valid model tests of the flow-induced vibration of reactor internals are identified. Test results on reactor internals flow vibration models are presented and compared with plant test results. Reactor internals with neutron pads are shown to vibrate only about one-third as much as internals having a thermal shield. 17 references

[en] This book explores methods of designing, implementing, and gaining political support -- both domestically and internationally -- for strategies and policies to reduce greenhouse gases. The book frames the issue and assesses the economic, policy, and management tradeoffs involved in designing strategies for international agreements, developing and implementing the means to enforce international agreements, comparing alternative policy responses, transferring technology from developed to developing countries, and making the transition from an international agreement to a domestic agenda to implement that agreement. Rather than promote specific options, the authors present a strategic framework from which specific alternatives can be assessed and compared, and offer guidance and advice that will be essential throughout the decade

[en] For better understanding of reaction rates for radioactive isotopes relevant for the nu-p process, we directly measured cross sections of 56,59Ni(n,p), 59Co(n,p), and 59Ni(n,α ) using the LENZ (Low Energy NZ) instruments at the Los Alamos Neutron Science Center (LANSCE). I will discuss the impacts of updated experimental reaction rates in the nu-p process nucleosynthesis for the context of answering to heavy element production puzzles. As a continued effort of improving nuclear reaction studies on radionuclides at LANSCE, I will present the progress on the dedicated solenoidal spectrometer for directly measuring neutron induced charged particle reactions with highly radioactive targets. This development is aimed to provide improved precision than the current LENZ instruments for various nuclear application’s data needs. This work benefits from the LANSCE accelerator facility and is supported by the U.S. Department of Energy under contracts DE-AC52-06NA25396 and the U.S. Department of Energy Office of Science-Nuclear Physics.

[en] The growth and dissolution behavior of oxide film on abraded pure Al has been investigated using cyclic polarization and has been found to be highly dependent on solution chemistry and temperature. The nature of the anions, borate, chromate, phosphate, and sulfate, at pH 3 to 11, and temperatures 0 to 60 C were examined. In near neutral solutions the dissolution behavior was greatly affected by each anion. In borate and chromate solutions at near neutral pH and room temperature, the currents continued to decrease with each subsequent cycle due to oxide thickening. In contrast, a significant rate of oxide dissolution occurred to produce reproducible repetitive curves during subsequent cycles in a phosphate and sulfate. Sulfate also produced a distinctly different mode during high field oxide growth. In increasing acidic (pH and lt; 4) or basic (pH and gt;9) solutions the oxide dissolution rate increased rapidly. The oxide dissolution rate was always enhanced with increasing temperature. At high pH (and gt;9) or elevated temperature (60 C), a current maximum was observed in chromate, due to a diffusion controlled monochromate ion enhanced dissolution reaction at the oxide/solution interface

[en] Results of three-dimensional Monte Carlo calculation of low energy flux of atmospheric neutrinos are presented and compared with earlier one-dimensional calculations 1,2 valid at higher neutrino energies. These low energy neutrinos are the atmospheric background in searching for neutrinos from astrophysical sources. Primary cosmic rays produce the neutrino flux peaking at near E sub=40 MeV and neutrino intensity peaking near E sub v=100 MeV. Because such neutrinos typically deviate by 20 to 30 degrees from the primary cosmic ray direction, three-dimensional effects are important for the search of atmospheric neutrinos. Nevertheless, the background of these atmospheric neutrinos is negligible for the detection of solar and supernova neutrinos

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[en] High temperature radiation sources exceeding one hundred eV can be produced via z-pinches using currently available pulsed power. The usual approach to compare the z-pinch simulation and experimental data is to convert the radiation output at the source, whose temperature and density distributions are computed from the 2-D MHD code, into simulated data such as a spectrometer reading. This conversion process involves a radiation transfer calculation through the axially symmetric source, assuming local thermodynamic equilibrium (LTE), and folding the radiation that reaches the detector with the frequency-dependent response function. In this paper the authors propose a different approach by which they can determine the temperature and density distributions of the radiation source directly from the spatially resolved spectral data. This unfolding process is reliable and unambiguous for the ideal case where LTE holds and the source is axially symmetric. In reality, imperfect LTE and axial symmetry will introduce inaccuracies into the unfolded distributions. The authors use a parameter optimization routine to find the temperature and density distributions that best fit the data. They know from their past experience that the radiation source resulting from the implosion of a thin foil does not exhibit good axial symmetry. However, recent experiments carried out at Sandia National Laboratory using multiple wire arrays were very promising to achieve reasonably good symmetry. For these experiments the method will provide a valuable diagnostic tool