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U.S.-European Union Trade Relations: Issues and Policy Challenges (open access)

U.S.-European Union Trade Relations: Issues and Policy Challenges

None
Date: April 6, 2005
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
Cosmos++: Relativistic Magnetohydrodynamics on Unstructured Grids with Local Adaptive Refinement (open access)

Cosmos++: Relativistic Magnetohydrodynamics on Unstructured Grids with Local Adaptive Refinement

A new code and methodology are introduced for solving the fully general relativistic magnetohydrodynamic (GRMHD) equations using time-explicit, finite-volume discretization. The code has options for solving the GRMHD equations using traditional artificial-viscosity (AV) or non-oscillatory central difference (NOCD) methods, or a new extended AV (eAV) scheme using artificial-viscosity together with a dual energy-flux-conserving formulation. The dual energy approach allows for accurate modeling of highly relativistic flows at boost factors well beyond what has been achieved to date by standard artificial viscosity methods. it provides the benefit of Godunov methods in capturing high Lorentz boosted flows but without complicated Riemann solvers, and the advantages of traditional artificial viscosity methods in their speed and flexibility. Additionally, the GRMHD equations are solved on an unstructured grid that supports local adaptive mesh refinement using a fully threated oct-tree (in three dimensions) network to traverse the grid hierarchy across levels and immediate neighbors. A number of tests are presented to demonstrate robustness of the numerical algorithms and adaptive mesh framework over a wide spectrum of problems, boosts, and astrophysical applications, including relativistic shock tubes, shock collisions, magnetosonic shocks, Alfven wave propagation, blast waves, magnetized Bondi flow, and the magneto-rotational instability in Kerr black hole spacetimes.
Date: May 6, 2005
Creator: Anninos, P; Fragile, P C & Salmonson, J D
Object Type: Article
System: The UNT Digital Library
The European Parliament (open access)

The European Parliament

The European Parliament (EP) is one of the three key institutions of the European Union (EU), and the only EU institution whose members are directly elected. This report discusses the construction and history of the EP, its role in functions of the EU as well as internationally, various international supports and criticisms of the EP, and the EP's ties with the U.S. Congress.
Date: April 6, 2005
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
Measurement of CP Asymmetries for the Decays B^+/- --> D^0_CP K*^+/- (open access)

Measurement of CP Asymmetries for the Decays B^+/- --> D^0_CP K*^+/-

Using a sample of 232 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II B Factory in 1999-2004, they study B{sup -} {yields} K{sup 0}K*(892){sup -} decays where K*{sup -} {yields} K{sub S}{sup 0} {pi}{sup -} and D{sup 0} {yields} K{sup -}{pi}{sup +}, K{sup -}{pi}{sup +}{pi}{sup 0}, K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} (non-CP final states); K{sup +}K{sup -}, {pi}{sup +}{pi}{sup -} (CP+ eigenstates); K{sub S}{sup 0}{pi}{sup 0}, K{sub S}{sup 0}{phi} and K{sub S}{sup 0}{omega} (CP- eigenstates). They measure four observables that are sensitive to the angle {gamma} of the CKM unitarity triangle; the partial-rate charge asymmetries A{sub CP{+-}} and the ratios of the B-decay branching fraction in CP{+-} and non-CP decays R{sub CP{+-}}: A{sub CP+} = -0.08 {+-} 0.19 (stat.) {+-} 0.08 (syst.); A{sub CP-} = -0.26 {+-} 0.40 (stat.) {+-} 0.12 (syst.); R{sub CP+} = 1.96 {+-} 0.40 (stat.) {+-} 0.11 (syst.); R{sub CP-} = 0.65 {+-} 0.26 (stat.) {+-} 0.08 (syst.).
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the $B^+\rightarrow p \bar{p} K^{+}$ Branching Fraction and Study of the Decay Dynamics (open access)

Measurement of the $B^+\rightarrow p \bar{p} K^{+}$ Branching Fraction and Study of the Decay Dynamics

With a sample of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector, we study the decay B{sup +} {yields} p{bar p}K{sup +} excluding charmonium decays to p{bar p}. We measure a branching fraction {Beta}(B{sup +} {yields} p{bar p}K{sup +}) = (6.7 {+-} 0.5 {+-} 0.4) x 10{sup -6}. An enhancement at low p{bar p} mass is observed and the Dalitz plot asymmetry suggests dominance of the penguin amplitude in this B decay. We search for a pentaquark candidate {Theta}*{sup ++} decaying into pK{sup +} in the mass range 1.43 to 2.00 GeV/c{sup 2} and set limits on {Beta}(B{sup +} {yields} {Theta}*{sup ++} {bar p}) x {Beta}({Theta}*{sup ++} {yields} pK{sup +}) at the 10{sup -7} level.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Partial Branching Fraction for Inclusive Charmless Semileptonic B Decays and Extraction of |Vub| (open access)

Measurement of the Partial Branching Fraction for Inclusive Charmless Semileptonic B Decays and Extraction of |Vub|

Charmless semileptonic decays, {bar B} {yields} X{sub u}{ell}{bar {nu}}, are studied in a sample of 232 million B{bar B} decays recorded with the BABAR detector, in events where the decay of the second B meson is fully reconstructed. Inclusive charmless decays are selected in kinematic regions where the dominant background from semileptonic B decays to charm is reduced by requirements on the hadronic mass M{sub X} and the momentum transfer q{sup 2}. The partial branching fraction for {bar B} {yields} X{sub u}{ell}{bar {nu}} decays for M{sub X} < 1.7 GeV/c{sup 2} and q{sup 2} > 8 GeV{sup 2}/c{sup 4} is measured to be {Delta}{Beta}({bar b} {yields} X{sub u}{ell}{bar {nu}}) = (0.87 {+-} 0.09{sub stat} {+-} 0.09{sub sys} {+-} 0.01{sub th}) x 10{sup -3}. The CKM matrix element|V{sub ub}| is determined by using theoretical calculations of phase space acceptances. Theoretical uncertainties in this extrapolation are reduced by using the inclusive b {yields} s{gamma} photon spectrum and moments of the b {yields} c{ell}{bar {nu}} lepton energy and hadronic invariant mass.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Time-Dependent CP Asymmetries and the CP-Odd Fraction in the Decay B0->D*+D*- (open access)

Measurement of Time-Dependent CP Asymmetries and the CP-Odd Fraction in the Decay B0->D*+D*-

We present an updated measurement of time-dependent CP asymmetries and the CP-odd fraction in the decay B{sup 0} D*{sup +}D*{sup -} using 232 x 10{sup 6} B{bar B} pairs collected by the BABAR detector at the PEP-II B factory. We determine the CP-odd fraction to be 0.125 {+-} 0.044(stat) {+-} 0.007(syst). The time-dependent CP asymmetry parameters C{sub +} and S{sub +} are determined to be 0.06 {+-} 0.17(stat) {+-} 0.03(syst) and -0.75 {+-} 0.25(stat) {+-} 0.03(syst), respectively. The Standard Model predicts these parameters to be 0 and -sin2{beta}, respectively, in the absence of penguin amplitude contributions.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurements of the Rare Decays B -> Kl+l- and B ->K*l+l- (open access)

Measurements of the Rare Decays B -> Kl+l- and B ->K*l+l-

The authors present measurements of the flavor-changing neutral current decays B {yields} K{ell}{sup +}{ell}{sup -} and B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pair. The data sample comprises 229 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Observation of a Broad Structure in the $\pi^+\pi^-J/\psi$ Mass Spectrum around 4.26~GeV/$c^2$ (open access)

Observation of a Broad Structure in the $\pi^+\pi^-J/\psi$ Mass Spectrum around 4.26~GeV/$c^2$

The authors study initial-state radiation events, e{sup +}e{sup -} {yields} {gamma}{sub ISR} {pi}{sup +}{pi}{sup -} J/{psi}, with data collected with the BABAR detector. They observe an accumulation of events near 4.26 GeV/c{sup 2} in the invariant-mass spectrum of {pi}{sup +}{pi}{sup -} J/{psi}. Fits of the mass spectrum indicate that a broad resonance with a mass of about 4.26 GeV/c{sup 2} is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90 MeV/c{sup 2}, depending on the fit hypothesis.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
A Precision Measurement of the Lambda_c Baryon Mass (open access)

A Precision Measurement of the Lambda_c Baryon Mass

The {Lambda}{sub c}{sup +} baryon mass is measured using {Lambda}{sub c}{sup +} {yields} {Lambda}K{sub S}{sup 0}K{sup +} and {Lambda}{sub c}{sup +} {yields} {Sigma}{sup 0}K{sub S}{sup 0}K{sup +} decays reconstructed in 232 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. The {Lambda}{sub c}{sup +} mass is measured to be 2286.46 {+-} 0.14 MeV/c{sup 2}. The dominant systematic uncertainties arise from the amount of material in the tracking volume and from the magnetic field strength.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Search for B- -> Ds+(*)- Phi (open access)

Search for B- -> Ds+(*)- Phi

We report on searches for B{sup -} {yields} D{sub S}{sup -}{phi} and B{sup -} {yields} D*{sub S}{sup -}{phi}. In the context of the Standard Model the branching fractions for these decays are expected to be highly suppressed, since they proceed through annihilation of the b and {bar u} quarks in the B{sup -} meson. Our results are based on 234 million {Upsilon}(42) {yields} B{bar B} decays collected with the BABAR detector at SLAC. We find no evidence for these decays, and we set 90% confidence level upper limits on the branching fractions {Beta}(B{sup -} {yields} D{sub S}{sup -}{phi}) < 1.8 x 10{sup -6}; {Beta}(B{sup -} {yields} D*{sub S}{sup -}{phi}) < 1.1 x 10{sup -5}. These results are consistent with Standard Model expectations.
Date: July 6, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Oil and Gas: Supply Issues After Katrina (open access)

Oil and Gas: Supply Issues After Katrina

None
Date: September 6, 2005
Creator: Bamberger, Robert L. & Kumins, Lawrence C.
Object Type: Report
System: The UNT Digital Library
Banyan 1.7 Compliance Manager Rough Guide Version 1.4 (open access)

Banyan 1.7 Compliance Manager Rough Guide Version 1.4

None
Date: September 6, 2005
Creator: Barter, R H
Object Type: Report
System: The UNT Digital Library
High-resolution ab-initio three-dimensional coherence X-ray diffraction microscopy (open access)

High-resolution ab-initio three-dimensional coherence X-ray diffraction microscopy

Three-dimensional diffraction microscopy offers the potential for high-resolution aberration-free diffraction-limited 3D images without the resolution and depth-of-field limitations of lens-based tomographic systems. Critical issues in obtaining a high-quality image include: (1) Data collection--signal to noise, system stability, dynamic range, automation; (2) Alignment of diffraction patterns with respect to one another; (3) Assembly of the diffraction data into a diffraction volume; and (4) Efficient algorithms for applying phase retrieval techniques to the diffraction volume; (5) Stability of the three-dimensional phase retrieval process; (6) Techniques for determining the object support; and (7) Treatment of missing data, both within the beamstop region and elsewhere. They have obtained high-quality 3D reconstructions from X-ray diffraction data alone. This is an important step, as it does not require a low-resolution image to fill in the beamstop region.
Date: June 6, 2005
Creator: Barty, A.
Object Type: Article
System: The UNT Digital Library
Political Status of Puerto Rico:  Background, Options, and Issues in the 109th Congress (open access)

Political Status of Puerto Rico: Background, Options, and Issues in the 109th Congress

None
Date: June 6, 2005
Creator: Bea, Keith
Object Type: Report
System: The UNT Digital Library
The Canadian Hog Trade Dispute (open access)

The Canadian Hog Trade Dispute

United States and Canada's hog industry, noting how live Canadian hogs do not affect the U.S hog business.
Date: April 6, 2005
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
Mad Cow Disease: Agricultural Issues for Congress (open access)

Mad Cow Disease: Agricultural Issues for Congress

This report includes information regarding various agriculture issues surrounding mad cow disease. Topics of discussion include risk analysis, safeguards, and trade issues.
Date: October 6, 2005
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
The Cost of Iraq, Afghanistan and Enhanced Base Security since 9/11 (open access)

The Cost of Iraq, Afghanistan and Enhanced Base Security since 9/11

Since the 9/11 terrorist attacks, CRS estimates that the Administration has allocated a total of about $357 billion for military operations, reconstruction, embassy costs, and various foreign aid programs in Iraq and Afghanistan, and for enhanced security at defense bases. This total includes $45 billion in “bridge” funding for the Department of Defense (DOD) as provided in H.J.Res. 68 /P.L.109- 77, a FY2006 Continuing Resolution, which was signed by the President on September 30, 2005.
Date: October 6, 2005
Creator: Belasco, Amy
Object Type: Report
System: The UNT Digital Library
Numerical Study of Field-reversed Configurations: The Formation and Ion Spin-up (open access)

Numerical Study of Field-reversed Configurations: The Formation and Ion Spin-up

Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs, and the new FRC formation method by counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good qualitative agreement with results from the SSX-FRC experiment. The simulations show formation of an FRC in about 20-30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects.
Date: June 6, 2005
Creator: Belova, E. V.; Davidson, R. C.; Ji, H.; Yamada, M.; Cothran, C. D.; Brown, M. R. et al.
Object Type: Report
System: The UNT Digital Library
Measurement of Pressure Dependent Fluorescence Yield of Air: Calibration Factor for UHECR Detectors (open access)

Measurement of Pressure Dependent Fluorescence Yield of Air: Calibration Factor for UHECR Detectors

In a test experiment at the Final Focus Test Beam of the Stanford Linear Accelerator Center, the fluorescence yield of 28.5 GeV electrons in air and nitrogen was measured. The measured photon yields between 300 and 400 nm at 1 atm and 29 C are Y(760 Torr){sup air} = 4.42 {+-} 0.73 and Y(760 Torr){sup N{sub 2}} = 29.2 {+-} 4.8 photons per electron per meter. Assuming that the fluorescence yield is proportional to the energy deposition of a charged particle traveling through air, good agreement with measurements at lower particle energies is observed.
Date: July 6, 2005
Creator: Belz, J. W.; Burt, G. W.; Cao, Z.; Chang, F. Y.; Chen, C. C.; Chen, C. W. et al.
Object Type: Article
System: The UNT Digital Library
Dijet event shapes as diagnostic tools (open access)

Dijet event shapes as diagnostic tools

Event shapes have long been used to extract information about hadronic final states and the properties of QCD, such as particle spin and the running coupling. Recently, a family of event shapes, the angularities, has been introduced that depends on a continuous parameter. This additional parameter-dependence further extends the versatility of event shapes. It provides a handle on nonperturbative power corrections, on non-global logarithms, and on the flow of color in the final state.
Date: May 6, 2005
Creator: Berger, Carola F.
Object Type: Article
System: The UNT Digital Library
Bootstrapping Multi-Parton Loop Amplitudes in QCD (open access)

Bootstrapping Multi-Parton Loop Amplitudes in QCD

The authors present a new method for computing complete one-loop amplitudes, including their rational parts, in non-supersymmetric gauge theory. This method merges the unitarity method with on-shell recursion relations. It systematizes a unitarity-factorization bootstrap approach previously applied by the authors to the one-loop amplitudes required for next-to-leading order QCD corrections to the processes e{sup +}e{sup -} {yields} Z, {gamma}* {yields} 4 jets and pp {yields} W + 2 jets. We illustrate the method by reproducing the one-loop color-ordered five-gluon helicity amplitudes in QCD that interfere with the tree amplitude, namely A{sub 5;1}(1{sup -}, 2{sup -}, 3{sup +}, 4{sup +}, 5{sup +}) and A{sub 5;1}(1{sup -}, 2{sup +}, 3{sup -}, 4{sup +}, 5{sup +}). Then we describe the construction of the six- and seven-gluon amplitudes with two adjacent negative-helicity gluons, A{sub 6;1}(1{sup -}, 2{sup -}, 3{sup +}, 4{sup +}, 5{sup +}, 6{sup +}) and A{sub 7;1}(1{sup -}, 2{sup -}, 3{sup +}, 4{sup +}, 5{sup +}, 6{sup +}, 7{sup +}), which uses the previously-computed logarithmic parts of the amplitudes as input. They present a compact expression for the six-gluon amplitude. No loop integrals are required to obtain the rational parts.
Date: July 6, 2005
Creator: Bern, Zvi; Dixon, Lance J. & Kosower, David A.
Object Type: Article
System: The UNT Digital Library
Ignition Target Fabrication and Fielding for the National Ignition Facility (open access)

Ignition Target Fabrication and Fielding for the National Ignition Facility

Continued advances in the design of ignition targets have stimulating new development paths for target fabrication, with potentially important simplifications for fielding cryogenic ignition targets for the National Ignition Facility. Including graded dopants in ablators as well as optimizing capsule and fuel layer dimensions increase implosion stability. This has led to developments of micron-scale fill tubes to fill and field the targets. Rapid progress has been made in development of the graded dopant layers in capsules as well as their characterization, in fabrication methods for micro-fill-tubes, and in fuel fill control with these fill tubes. Phase-contrast x-ray radiography has allowed characterization of fuel layers in beryllium targets. This target development program includes participation from General Atomics, Lawrence Livermore National Laboratory, and Los Alamos National Laboratory.
Date: October 6, 2005
Creator: Bernat, T. P.; Huang, H.; Nikroo, A.; Stephens, R.; Wilkens, H.; Xu, H. et al.
Object Type: Article
System: The UNT Digital Library
Fuel Cell Demonstration Project - 200 kW - Phosphoric Acid Fuel Cell Power Plant Located at the National Transportation Research Center: FINAL REPORT (open access)

Fuel Cell Demonstration Project - 200 kW - Phosphoric Acid Fuel Cell Power Plant Located at the National Transportation Research Center: FINAL REPORT

Oak Ridge National Laboratory (ORNL) researches and develops distributed generation technology for the Department of Energy, Energy Efficiency and Renewable Energy Distributed Energy Program. This report describes installation and operation of one such distributed generation system, a United Technology Corporation fuel cell located at the National Transportation Research Center in Knoxville, Tennessee. Data collected from June 2003 to June of 2004, provides valuable insight regarding fuel cell-grid compatibility and the cost-benefit of the fuel cell operation. The NTRC fuel cell included a high-heat recovery option so that use of thermal energy improves project economics and improves system efficiency to 59% year round. During the year the fuel cell supplied a total of 834MWh to the NTRC and provided 300MBtu of hot water. Installation of the NTRC fuel cell was funded by the Distributed Energy Program with partial funding from the Department of Defense's Climate Change Fuel Cell Buy Down Program, administered by the National Energy Technology Laboratory. On-going operational expenses are funded by ORNL's utility budget and are paid from operational cost savings. Technical information and the benefit-cost of the fuel cell are both evaluated in this report and sister reports.
Date: May 6, 2005
Creator: Berry, JB
Object Type: Report
System: The UNT Digital Library