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J/(ps) Production via Initial State Radiation in e+e- ----> (m)+(m)-y at an e+e- Center-of-Mass Energy near 10.6 GeV

Description: The authors have used a study of the process e{sup +}e{sup -} {yields} {mu}{sup +}{mu}{sup -} {gamma} at a center-of-mass energy near the {Upsilon}(4S) resonance for a {mu}{sup +}{mu}{sup -} invariant mass range near the J/{psi} mass to extract the cross section {sigma}(e{sup +}e{sup -} {yields} J/{psi}{gamma} {yields} {mu}{sup +}{mu}{sup -}{gamma}). The data set, corresponding to an integrated luminosity of 88.4 fb{sup -1}, was collected using the BABAR detector at the PEP-II collider. They me… more
Date: November 13, 2003
Creator: Wright, D & Collaboration, T B
Partner: UNT Libraries Government Documents Department
open access

Anodic Behavior of Alloy 22 in Calcium Chloride and in Calcium Chloride Plus Calcium Nitrate Brines

Description: Alloy 22 (UNS N60622) is a nickel-based alloy, which is extensively used in aggressive industrial applications, especially due to its resistance to localized corrosion and stress corrosion cracking in high chloride environments. The purpose of this work was to characterize the anodic behavior of Alloy 22 in concentrated calcium chloride (CaCl{sub 2}) brines and to evaluate the inhibitive effect of nitrate, especially to localized corrosion. Standard electrochemical tests such as polarization re… more
Date: May 13, 2003
Creator: Evans, K. J.; Day, S. D.; Ilevbare, G. O.; Whalen, M. T.; King, K. J.; Hust, G. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Comparison of up-scaling methods in poroelasticity and its generalizations

Description: Four methods of up-scaling coupled equations at the microscale to equations valid at the mesoscale and/or macroscale for fluid-saturated and partially saturated porous media will be discussed, compared, and contrasted. The four methods are: (1) effective medium theory, (2) mixture theory, (3) two-scale and multiscale homogenization, and (4) volume averaging. All these methods have advantages for some applications and disadvantages for others. For example, effective medium theory, mixture theory… more
Date: December 13, 2003
Creator: Berger, E. L.
Partner: UNT Libraries Government Documents Department
open access

Stochastic Kinetic Monte Carlo algorithms for long-range Hamiltonians

Description: We present a higher order kinetic Monte Carlo methodology suitable to model the evolution of systems in which the transition rates are non- trivial to calculate or in which Monte Carlo moves are likely to be non- productive flicker events. The second order residence time algorithm first introduced by Athenes et al.[1] is rederived from the n-fold way algorithm of Bortz et al.[2] as a fully stochastic algorithm. The second order algorithm can be dynamically called when necessary to eliminate unp… more
Date: October 13, 2003
Creator: Mason, D R; Rudd, R E & Sutton, A P
Partner: UNT Libraries Government Documents Department
open access

Proton Beam Focusing and Heating in Petawatt Laser-Solid Interactions

Description: It has recently been demonstrated that femtosecond-laser generated proton beams may be focused. These protons, following expansion of the Debye sheath, emit off the inner concave surface of hemispherical shell targets irradiated at their outer convex pole. The sheath normal expansion produces a rapidly converging proton beam. Such focused proton beams provide a new and powerful means to achieve isochoric heating to high temperatures. They are potentially important for measuring the equation of … more
Date: August 13, 2003
Creator: Snavely, R. A.; Gu, P.; King, J.; Hey, D.; Akli, K.; Zhang, B. B. et al.
Partner: UNT Libraries Government Documents Department
open access

Multivariate Clustering of Large-Scale Scientific Simulation Data

Description: Simulations of complex scientific phenomena involve the execution of massively parallel computer programs. These simulation programs generate large-scale data sets over the spatio-temporal space. Modeling such massive data sets is an essential step in helping scientists discover new information from their computer simulations. In this paper, we present a simple but effective multivariate clustering algorithm for large-scale scientific simulation data sets. Our algorithm utilizes the cosine simi… more
Date: June 13, 2003
Creator: Eliassi-Rad, T & Critchlow, T
Partner: UNT Libraries Government Documents Department
open access

Implications of Convective Scrape-Off Layer Transport for Fusion Reactors with Solid and Liquid Walls

Description: Recent experimental observations in tokamaks indicate enhanced convection of plasma blobs toward the main chamber wall. Potential implications of these observations for reactors are examined here. Two dimensional plasma edge calculations are performed with UEDGE, including convective transport consistent with present experiments. This is coupled to a kinetic neutral calculation using the code NUT, to compute the hot neutral flux to the wall. The inclusion of convection increases sputtering of t… more
Date: November 13, 2003
Creator: Kotschenreuther, M; Rognlien, T D & Valanju, P
Partner: UNT Libraries Government Documents Department
open access

The National Ignition Facility: The World's Largest Laser

Description: The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. When completed, NIF will be the world's largest and most energetic laser experimental system, providing an international center to study inertial confinement fusion and the physics… more
Date: October 13, 2003
Creator: Moses, E I
Partner: UNT Libraries Government Documents Department
open access

A Hidden Twelve-Dimensional SuperPoincare Symmetry In Eleven Dimensions

Description: First, we review a result in our previous paper, of how a ten-dimensional superparticle, taken off-shell, has a hidden eleven-dimensional superPoincare symmetry. Then, we show that the physical sector is defined by three first-class constraints which preserve the full eleven-dimensional symmetry. Applying the same concepts to the eleven dimensional superparticle, taken off-shell, we discover a hidden twelve dimensional superPoincare symmetry that governs the theory.
Date: December 13, 2003
Creator: Bars, Itzhak; Deliduman, Cemsinan; Pasqua, Andrea & Zumino, Bruno
Partner: UNT Libraries Government Documents Department
open access

Numerical simulation of leakage from a geologic disposal reservoirfor CO2, with transitions between super- and sub-criticalconditions

Description: The critical point of CO2 is at temperature and pressureconditions of Tcrit = 31.04oC, Pcrit = 73.82 bar. At lower (subcritical)temperatures and/or pressures, CO2 can exist in two different phases, aliquid and a gaseous state, as well as in two-phase mixtures of thesestates. Disposal of CO2 into brine formations would be made atsupercritical pressures. However, CO2 escaping from the storage reservoirmay migrate upwards towards regions with lower temperatures andpressures, where CO2 would be in … more
Date: April 13, 2003
Creator: Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

Proof-of-concept experiments for negative ion driver beams forheavy ion fusion

Description: Negative halogen ion beams have recently been proposed as heavy ion fusion drivers. They would avoid the problem of electron accumulation in positive ion beams, and could be efficiently photodetached to neutrals if desired [1]. Initial experiments using chlorine produced a current density of 45 mA/cm{sup 2} of 99.5% atomic negative Cl with an e/Cl{sup -} ratio as low as 7:1 and good emittance.
Date: May 13, 2003
Creator: Grisham, L. R.; Hahto, S. K.; Hahto, S. T.; Kwan, J. W. & Leung, K. N.
Partner: UNT Libraries Government Documents Department
open access

A MODEL FOR PRODUCING STABLE, BROADBAND TERAHERTZ COHERENT SYNCHROTRONRADIATION IN STORAGE RINGS

Description: We present a model for producing stable broadband coherent synchrotron radiation (CSR) in the terahertz frequency region in an electron storage ring. The model includes distortion of bunch shape from the synchrotron radiation (SR), enhancing higher frequency coherent emission and limits to stable emission due to a microbunching instability excited by the SR. We use this model to optimize the performance of a source for CSR emission.
Date: June 13, 2003
Creator: Sannibale, Fernando; Byrd, John M.; Loftsdottir, Agusta; Martin, MichaelC. & Venturini, Marco
Partner: UNT Libraries Government Documents Department
open access

Remote Inspection of a 46 Year Old Buried High Level Waste Storage Tank

Description: This paper provides a description of the remote ultrasonic examinations of a high level radioactive waste storage tank at the Savannah River Site. The inspections were performed from the contaminated, annular space of the 46 year old, inactive, 1.03 million gallon waste storage tank.
Date: May 13, 2003
Creator: Elder, J.B.
Partner: UNT Libraries Government Documents Department
open access

Phase motion of the scalar {pi}{pi} amplitudes in D{sup +}, D{sub s}{sup +} {yields} {pi}{sup -} {pi}{sup +}{pi}{sup +} decays

Description: We make a direct and model-independent measurement of the low {pi}{sup +} {pi}{sup -} mass phase motion in the D{sup +} {yields} {pi}{sup -} {pi}{sup +}{pi}{sup +} decay. Our preliminary results show a strong phase variation, compatible with the isoscalar {sigma}(500) meson. This result confirms our previous result [1] where we found evidence for the existence of this scalar particle using full Dalitz-plot analysis. We apply the Amplitude Difference (AD) method [2] to the same Fermilab E791 dat… more
Date: August 13, 2003
Creator: Bediaga, Ignacio
Partner: UNT Libraries Government Documents Department
open access

Systematic uncertainties on Delta m2 from neutrino physics, using calorimetric energy reconstruction

Description: This report describes how uncertainties in neutrino interactions, particularly at neutrino energies of a few GeV, can contribute to uncertainties in measurements of neutrino oscillation parameters for experiments using calorimetric devices. Uncertainties studied include those on final state multiplicities, cross sections, electron-hadron calorimeter differences, and nuclear rescattering.
Date: August 13, 2003
Creator: Harris, Deborah A.
Partner: UNT Libraries Government Documents Department
open access

Long baseline neutrino oscillations: Parameter degeneracies and JHF/NuMI complementarity

Description: A summary of the parameter degeneracy issue for long baseline neutrino oscillations is presented and how a sequence of measurements can be used to resolve all degeneracies. Next, a comparison of the JHF and NuMI Off-Axis proposals is made with emphasis on how both experiments running neutrinos can distinguish between the normal and inverted hierarchies provided the E/L of NuMI is less than or equal to the E/L of JHF. Due to the space limitations of this proceedings only an executive style summa… more
Date: October 13, 2003
Creator: Parke, Stephen; Minakata, Hisakazu & Nunokawa, Hiroshi
Partner: UNT Libraries Government Documents Department
open access

Underlying event studies at CDF

Description: We present recent studies about the ''underlying event'' which originates mostly from soft spectator interactions. First Run II data results are compared to published Run I results and to QCD Monte Carlo models.
Date: October 13, 2003
Creator: Lami, S.
Partner: UNT Libraries Government Documents Department
open access

The scalar {kappa} from D{sup +} {yields} K{sup -} {pi}{sup +}{pi}{sup +}: Further studies

Description: We briefly review the recent results obtained by Fermilab experiment E791 on the Dalitz plot analysis of the decay D{sup +} {yields} K{sup -} {pi}{sup +}{pi}{sup +}, where indication for a light K {pi} scalar resonance, the {kappa}, was found. We also present preliminary studies providing further information on the phase behavior of the scalar components at low mass, supporting the previous indication for the {kappa}.
Date: August 13, 2003
Creator: Gobel, Carla
Partner: UNT Libraries Government Documents Department
open access

Automated Mass Calibration and Measurement Control Program

Description: Mass and weight standards calibration costs have been reduced by 50 percent and the measurement quality improved at the Department of Energy's Savannah River Site's Savannah River Standard's Laboratory.
Date: January 13, 2003
Creator: Jones, J.D.
Partner: UNT Libraries Government Documents Department
open access

Elastic properties of supported polycrystalline thin films and multilayers: An X-ray diffraction study

Description: Numerous experimental and theoretical studies have shown that thin film elastic behavior may be different from the bulk one due to size effects related to grain boundaries, free surfaces and interfaces. In addition, thin films often present high compressive residual stresses which may be responsible of thin film buckling. These two features will be discussed in this communication through recent x-ray diffraction experiments: in situ tensile testing for elastic constant analysis and scanning x-r… more
Date: August 13, 2003
Creator: Goudeau, P.; Villain, P.; Tamura, N.; Renault, P.-O.; Badawi, K.F. & Padmore, H.A.
Partner: UNT Libraries Government Documents Department
open access

Charm and beauty at the Tevatron

Description: The large heavy quark production cross section in p{bar p} collisions makes the Tevatron an excellent place to study charm and bottom physics. This allows for a rich program of spectroscopy, CP parameter measurements, and searches for new physics.
Date: October 13, 2003
Creator: Cranshaw, J.
Partner: UNT Libraries Government Documents Department
open access

A normalized-cut algorithm for hierarchical vector field data segmentation

Description: In the context of vector field data visualization, it is often desirable to construct a hierarchical data representation. One possibility to construct a hierarchy is based on clustering vectors using certain similarity criteria. We combine two fundamental approaches to cluster vectors and construct hierarchical vector field representations. For clustering, a locally constructed linear least-squares approximation is incorporated into a similarity measure that considers both Euclidean distance be… more
Date: January 13, 2003
Creator: Chen, Jiann-Liang; Bai, Zhaojun; Hamann, Bernd & Ligocki, Terry J.
Partner: UNT Libraries Government Documents Department
open access

["The New Face of Gay Power" article, October 13, 2003]

Description: An article, written by John Cloud for Time Magazine, about Cody, Wyoming five years after the murder of a young gay man named Matthew Shepard. It is one of the more liberal cities in the state and is also home to one of the Republican Unity Coalition's chairmen, Alan Simpson.
Date: October 13, 2003
Creator: Cloud, John
Partner: UNT Libraries Special Collections
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