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Nuclear Electric Dipole Moment of 3He

Description: A permanent electric dipole moment (EDM) of a physical system would require time-reversal (T) violation, which is equivalent to charge-conjugation-parity (CP) violation by CPT invariance. Experimental programs are currently pushing the limits on EDMs in atoms, nuclei, and the neutron to regimes of fundamental theoretical interest. Nuclear EDMs can be studied at ion storage rings with sensitivities that may be competitive with atomic and neutron measurements. Here we calculate the magnitude of t… more
Date: April 8, 2008
Creator: Stetcu, I; P.Liu, C; Friar, J L; Hayes, A C & Navratil, P
Partner: UNT Libraries Government Documents Department
open access

Supercomputers: Super-polluters?

Description: Thanks to imperatives for limiting waste heat, maximizing performance, and controlling operating cost, energy efficiency has been a driving force in the evolution of supercomputers. The challenge going forward will be to extend these gains to offset the steeply rising demands for computing services and performance.
Date: April 8, 2008
Creator: Mills, Evan; Mills, Evan; Tschudi, William; Shalf, John & Simon, Horst
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

Description: The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%… more
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Progress of the PEP-II B-Factory

Description: No Description Available.
Date: April 8, 2008
Creator: Seeman, J.; Browne, Michael C.; Cai, Y.; Colocho, W.; Decker, F.J.; Donald, M. et al.
Partner: UNT Libraries Government Documents Department
open access

A Detailed Chemical Kinetic Reaction Mechanism for Oxidation of Four Small Alkyl Esters in Laminar Premixed Flames

Description: A detailed chemical kinetic reaction mechanism has been developed for a group of four small alkyl ester fuels, consisting of methyl formate, methyl acetate, ethyl formate and ethyl acetate. This mechanism is validated by comparisons between computed results and recently measured intermediate species mole fractions in fuel-rich, low pressure, premixed laminar flames. The model development employs a principle of similarity of functional groups in constraining the H atom abstraction and unimolecul… more
Date: February 8, 2008
Creator: Westbrook, C K; Pitz, W J; Westmoreland, P R; Dryer, F L; Chaos, M; Osswald, P et al.
Partner: UNT Libraries Government Documents Department
open access

CP Violation at BaBar

Description: Several new and updated BABAR measurements of sin 2{beta} are presented, together with the latest constraints on the Unitarity Triangle angles {alpha} and {gamma}. The higher statistics now available allow more sophisticated analysis techniques, such as time-dependent Dalitz plot fitting. Combined world-average results place tight constraints on the Unitarity Triangle. There is good agreement among the measurements and with the unitarity of the CKM matrix. This represents an impressive verifica… more
Date: January 8, 2008
Creator: Hawkes, Chris & U., /Birmingham
Partner: UNT Libraries Government Documents Department
open access

Temporal Dispersion of a Spectrometer

Description: The temporal dispersion of an optical spectrometer has been characterized for a variety of conditions related to optical diagnostics to be fielded at the National Ignition Facility (e.g., Full-Aperture Backscatter Station, Thomson Scattering). Significant time smear is introduced into these systems by the path length difference through the spectrometer. The temporal resolution can be calculated to depend only on the order of the grating, wavelength, and the number of grooves illuminated. To enh… more
Date: May 8, 2008
Creator: Visco, A; Drake, R P; Froula, D H & Glenzer, S H
Partner: UNT Libraries Government Documents Department
open access

AN INNOVATIVE APPROACH FOR CONSTRUCTING AN IN-SITU BARRIER FOR STRONTIUM-90 AT THE HANFORD SITE WASHINGTON

Description: Efforts to reduce the flux of Sr-90 to the Columbia River from Hanford Site 100-N Area past-practice liquid waste disposal sites have been underway since the early 1990s. Termination of all liquid discharges to the ground in 1993 was a major step toward meeting this goal. However, Sr-90 adsorbed on aquifer solids beneath liquid waste disposal sites and extending beneath the near-shore riverbed remains a continuing contaminant source to groundwater and the Columbia River. The initial pump-and-tr… more
Date: December 8, 2008
Creator: RJ, FABRE
Partner: UNT Libraries Government Documents Department
open access

Evidence against correlations between nuclear decay rates and Earth-Sun distance

Description: We have reexamined our previously published data to search for evidence of correlations between the rates for the alpha, beta-minus, beta-plus, and electron capture decays of 22Na, 44Ti, 108Agm, 121Snm, 133Ba, and 241Am and the Earth?Sun distance. We find no evidence for such correlations and set limits on the possible amplitudes of such correlations substantially smaller than those observed in previous experiments.
Date: December 8, 2008
Creator: Norman, Eric B.; Browne, Edgardo; Shugart, Howard A.; Joshi, Tenzing H. & Firestone, Richard B.
Partner: UNT Libraries Government Documents Department
open access

Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
Partner: UNT Libraries Government Documents Department
open access

Diagnostic Components in Harsh Radiation Environments: Possible Overlap in R&D Requirements of IC and MF Systems

Description: The next generation of large scale fusion devices--ITER/LMJ/NIF--will require diagnostic components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiation, and in some cases debris and shrapnel, at levels several orders of magnitude higher than those experienced in today's devices. For several years the question of possible synergy between inertia… more
Date: May 8, 2008
Creator: Bourgade, J. L.; Costley, A. E.; Reichle, R.; Hodgson, E. R.; Hsing, W.; Glebov, V. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of D^0-\overline{D^0} Mixing using the Ratio of Lifetimes for the Decays D^0 \to K^-\pi^+, K^-K^+, and \pi^-\pi^+

Description: The authors present a measurement of D{sup 0}-{bar D}{sup 0} mixing parameters using the ratios of lifetimes extracted from a sample of D{sup 0} mesons produced through the process D*{sup +} {yields} D{sup 0}{pi}{sup +}, that decay to K{sup -}{pi}{sup +}, I{sup -}K{sup +}, or {pi}{sup -}{pi}{sup +}. the Cabibbo-suppressed modes K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} are compared to the Cabibbo-favored mode K{sup -}{pi}{sup +} to obtain a measurement of ycp, which in the limit of CP conserv… more
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Design and Construction of Test Coils for the MICE Coupling Solenoid Magnet

Description: The superconducting coupling solenoid to be applied in the Muon Ionization Cooling Experiment (MICE) is made from copper matrix Nb-Ti conductors with inner radius of 750 mm, length of 285 mm and thickness of 102.5 mm at room temperature. The magnetic field up to 2.6 T at the magnet centerline is to keep the muons within the MICE RF cavities. Its self inductance is around 592 H and its magnet stored energy is about 13 MJ at a full current of 210 A for the worst operation case of the MICE channel… more
Date: August 8, 2008
Creator: Wang, Li; Pan, Heng; Xu, F.Y.; Liu, XioaKun; Chen, AnBin; Li, LanKai et al.
Partner: UNT Libraries Government Documents Department
open access

SAVANNAH RIVER NATIONAL LABORATORY HYDROGEN TECHNOLOGY RESEARCH

Description: The Savannah River National Laboratory (SRNL) is a U.S. Department of Energy research and development laboratory located at the Savannah River Site (SRS) near Aiken, South Carolina. SRNL has over 50 years of experience in developing and applying hydrogen technology, both through its national defense activities as well as through its recent activities with the DOE Hydrogen Programs. The hydrogen technical staff at SRNL comprises over 90 scientists, engineers and technologists, and it is believed… more
Date: February 8, 2008
Creator: Danko, E
Partner: UNT Libraries Government Documents Department
open access

In-situ monitoring of surface post-processing in large aperture fused silica optics with Optical Coherence Tomography

Description: Optical Coherence Tomography is explored as a method to image laser-damage sites located on the surface of large aperture fused silica optics during post-processing via CO{sub 2} laser ablation. The signal analysis for image acquisition was adapted to meet the sensitivity requirements for this application. A long-working distance geometry was employed to allow imaging through the opposite surface of the 5-cm thick optic. The experimental results demonstrate the potential of OCT for remote monit… more
Date: February 8, 2008
Creator: Guss, G M; Bass, I l; Hackel, R P; Mailhiot, C & Demos, S G
Partner: UNT Libraries Government Documents Department
open access

HAZARD ANALYSIS SOFTWARE

Description: Washington Safety Management Solutions, LLC developed web-based software to improve the efficiency and consistency of hazard identification and analysis, control selection and classification, and to standardize analysis reporting at Savannah River Site. In the new nuclear age, information technology provides methods to improve the efficiency of the documented safety analysis development process which includes hazard analysis activities. This software provides a web interface that interacts with… more
Date: April 8, 2008
Creator: Sommer, S & Tinh Tran, T
Partner: UNT Libraries Government Documents Department
open access

X-ray absorption study of the electronic structure of Mn-doped amorphous Si

Description: The electronic structure of Mn in amorphous Si (a-Mn{sub x}Si{sub 1?x}) is studied by X-ray absorption spectroscopy at the Mn L{sub 3,2} edges for x = 0.005-0.18. Except the x = 0.005 sample, which shows a slight signature of Mn{sup 2+} atomic multiplets associated with a local Mn moment, all samples have broad and featureless L{sub 3,2} absorption peaks, corresponding to an itinerant state for all 3d electrons. The broad X-ray absorption spectra exclude the possibility of a localized 3d moment… more
Date: March 8, 2008
Creator: Arenholz, Elke; Zeng, Li; Huegel, A.; Helgren, E.; Hellman, F.; Piamonteze, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of Onsite Transportation Safety Documents for Nevada Test Site

Description: Department of Energy (DOE) Orders require each DOE site to develop onsite transportation safety documents (OTSDs). The Nevada Test Site approach divided all onsite transfers into two groups with each group covered by a standalone OTSD identified as Non-Nuclear and Nuclear. The Non-Nuclear transfers involve all radioactive hazardous material in less than Hazard Category (HC)-3 quantities and all chemically hazardous materials. The Nuclear transfers involve all radioactive material equal to or gr… more
Date: May 8, 2008
Creator: Frank Hand, Willard Thomas, Frank Sciacca, Manny Negrete, Susan Kelley
Partner: UNT Libraries Government Documents Department
open access

Tests of Four PT-415 Coolers Installed in the Drop-in Mode

Description: The superconducting magnets and absorbers for MICE will be cooled using PT415 pulse tube coolers. The cooler 2nd stage will be connected to magnets and the absorbers through a helium or hydrogen re-condensing system. It was proposed that the coolers be connected to the magnets in such a way that the cooler can be easily installed and removed, which permits the magnets to be shipped without the coolers. The drop-in mode requires that the cooler 1st stage be well connected to the magnet shields a… more
Date: July 8, 2008
Creator: Green, Michael A. & Wang, S. T.
Partner: UNT Libraries Government Documents Department
open access

Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

Description: We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of th… more
Date: January 8, 2008
Creator: Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C. et al.
Partner: UNT Libraries Government Documents Department
open access

Transverse Effects Due to Random Displacement of Resistive Wall Segments and Focusing Elements

Description: In this paper, we study the single bunch transverse beam dynamics in the presence of random displacements of resistive wall segments and focusing elements. Analytical formulas are obtained for long-range resistive wall wake, together with numerical results for short-range resistive wall wake. The results are applied to the LCLS project and some other proposed accelerators.
Date: January 8, 2008
Creator: Delayen, J.R.; U., /Jefferson Lab /Old Dominion & Wu, J.
Partner: UNT Libraries Government Documents Department
open access

Autofluorescence dynamics during reperfusion following long-term renal ischemia in a rat model

Description: Optical properties of near-surface kidney tissue were monitored in order to assess response during reperfusion to long (20 minutes) versus prolonged (150 minutes) ischemia in an in vivo rat model. Specifically, autofluorescence images of the exposed surfaces of both the normal and the ischemic kidneys were acquired during both injury and reperfusion alternately under 355 nm and 266 nm excitations. The temporal profile of the emission of the injured kidney during the reperfusion phase under 355 … more
Date: February 8, 2008
Creator: Raman, R N; Pivetti, C D; Matthews, D L; Troppmann, C & Demos, S G
Partner: UNT Libraries Government Documents Department
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