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Thermal Fusing Model of Conducting Particle Composites

Description: Composites of carbon black particles in polyethylene are known to exhibit an unusually rapid increase in resistivity as the applied field is increased, making this material useful in automatically resettable fuses. In this application the composite is in series with the circuit it is protecting: at low applied voltages this circuit is the load, but at high applied voltages the composite becomes the load, limiting the current to the circuit. We present a simple model of this behavior in terms of… more
Date: June 24, 1999
Creator: Martin, James E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fast-neutrons incident on gadolinium.

Description: Reports in the Argonne National Laboratory Nuclear Data and Measurement Series present results of studies in the field of microscopic nuclear data. The primary objective of the series is the dissemination of information in the comprehensive form required for nuclear technology applications. This Series is devoted to: (a) measured microscopic nuclear parameters, (b) experimental techniques and facilities employed in measurements, (c) the analysis, correlation and interpretation of nuclear data, … more
Date: May 24, 2004
Creator: Smith, A. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scaling of Kinetic Instability Induced Fast Ion Losses in NSTX

Description: During neutral beam injection (NBI) in the National Spherical Torus Experiment (NSTX), a wide variety of fast ion driven instabilities is excited by the large ratio of fast ion velocity to Alfven velocity, together with the relatively high fast ion beta, beta(sub)f. The fast ion instabilities have frequencies ranging from a few kilohertz to the ion cyclotron frequency. The modes can be divided roughly into three categories, starting with Energetic Particle Modes (EPM) in the lowest frequency ra… more
Date: June 24, 2005
Creator: Fredrickson, E. D.; Darrow, D.; Medley, S.; Menard, J.; Park, H.; Roquemore, L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Femtosecond nonlinear spectroscopy at surfaces: Second-harmonic probing of hole burning at the Si(111)7x7 surface and fourier-transform sum-frequency vibrational spectroscopy

Description: The high temporal resolution and broad bandwidth of a femtosecond laser system are exploited in a pair of nonlinear optical studies of surfaces. The dephasing dynamics of resonances associated with the adatom dangling bonds of the Si(111)7 x 7 surface are explored by transient second-harmonic hole burning, a process that can be described as a fourth-order nonlinear optical process. Spectral holes produced by a 100 fs pump pulse at about 800 nm are probed by the second harmonic signal of a 100 f… more
Date: November 24, 2004
Creator: McGuire, John Andrew
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report

Description: Budget Period 2 of the East Binger Unit (''EBU'') DOE Project has been. Recent activities included additional data gathering and project monitoring, plus initiation of work on an SPE paper on the modeling efforts of the project. Early production performance suggests horizontal wells do not provide sufficient additional production over vertical wells to justify their incremental cost. It will take more time to evaluate the impact of the horizontal wells on sweep and ultimate recovery, but it is … more
Date: August 24, 2004
Creator: Sinner, Joe
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structure and Dynamics of Negative Ions

Description: This report describes progress made during the final three-year grant period 1997-2000. During this period, we experimentally investigated the structure and dynamics of negative ions by detaching the outermost electron in controlled processes induced by photon-, electron- and heavy particle-impact. In this manner we studied, at a fundamental level, the role of electron correlation in the structure and dynamics of simple, few-particle atomic systems. Our measurements have provided sensitive test… more
Date: October 24, 2000
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final state interaction phase in B decays

Description: From an estimate of the meson-meson inelastic scattering at 5 GeV it is concluded that a typical strong phase in B decays to two mesons is of order of 20{sup o}. For a particular final state an estimate of the phase depends on whether that state is more or less probable as a final state compared to those states to which it is connected by the strong interaction S matrix.
Date: March 24, 1999
Creator: Suzuki, Mahiko & Wolfenstein, Lincoln
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of Taus in ATLAS

Description: The total production rate for taus at a hadron collider is not a useful quantity. Taus must have significant transverse momentum (p{sub T}) in order to be observable. Leptonic decays of taus will yield isolated electrons or muons that can be detected but these can also be directly produced so discriminating their origin can be difficult. Hadronic decays of taus result in jets that must be distinguished from jets arising from QCD processes using the particle multiplicity and invariant mass. At t… more
Date: October 24, 2002
Creator: Hinchliffe, Ian
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear self-duality in even dimensions

Description: We show that the Born-Infeld theory with n complex abelian gauge fields written in an auxiliary field formulation has a U(n, n) duality group. We conjecture the form of the Lagrangian obtained by eliminating the auxiliary fields and then introduce a new reality structure leading to a Born-Infeld theory with n real gauge fields and an Sp(2n, IR) duality symmetry. The real and complex constructions are extended to arbitrary even dimensions. The maximal noncompact duality group is U(n, n) for comp… more
Date: March 24, 2000
Creator: Aschieri, Paolo; Brace, Daniel; Morariu, Bogdan & Zumino, Bruno
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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UNIVERSAL BEHAVIOR OF CHARGED PARTICLE PRODUCTION IN HEAVY ION COLLISIONS AT RHIC ENERGIES.

Description: The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at {radical}(s{sub NN}) = 19.6, 130 and 200 GeV. Two observations indicate universal behavior of charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/… more
Date: July 24, 2002
Creator: Steinberg, P. A. & COLLABORATION, FOR THE PHOBOS
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Conceptual Design of Pion Capture Magnets of Up to 15 Cm Bore and 20 T Peak Field.

Description: For the Neutrino Factory and Muon Collider Collaboration, BNL has considered solenoidal magnet systems of several types to capture pions generated by bombarding a mercury jet with multi-GeV protons. The magnet systems generate up to 20 T, uniform to 5% throughout a cylindrical volume 0.15 m in diameter and 0.6 m long. Axially downstream the field ramps gradually downward by a factor of sixteen, while the bore increases fourfold. The steady-state system needed for an accelerator has many superco… more
Date: September 24, 2001
Creator: Weggel, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Soft X-ray Tangential Imaging of the NSTX Core Plasma by Means of a MPGD Pin-hole Camera

Description: A fast X-ray system based on a Micro Pattern Gas Detector has been used, for the first time, to investigate emission from the plasma core of the National Spherical Tokamak eXperiment (NSTX) at the Princeton Plasma Physics Laboratory. The results presented in this work demonstrate the capability of such a device to measure with a time resolution of the order of 1 ms the curvature and the elongation of the X-ray iso-emissivity contours, under various plasma conditions. Also, comparisons with the … more
Date: July 24, 2003
Creator: Pacella, D.; Leigheb, M.; Bellazzini, R.; Brez, A.; Finkenthal, M.; Stutman, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The future of reactor neutrino experiments: A novel approach to measuring theta{sub 13}

Description: Results from non-accelerator neutrino oscillation experiments have provided evidence for the oscillation of massive neutrinos. The subdominant oscillation, the coupling of the electron neutrino flavor to the third mass eigenstate, has not been measured yet. The size of this coupling U{sub e3} and its corresponding mixing angle theta{sub 13} are critical for CP violation searches in the lepton sector and will define the future of accelerator neutrino physics. The current best limit on U{sub e3} … more
Date: August 24, 2003
Creator: Heeger, Karsten M.; Freedman, Stuart J. & Luk, Kam-Biu
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Causal inheritence in plane wave quotients

Description: We investigate the appearance of closed timelike curves in quotients of plane waves along spacelike isometries. First we formulate a necessary and sufficient condition for a quotient of a general spacetime to preserve stable causality. We explicitly show that the plane waves are stably causal; in passing, we observe that some pp-waves are not even distinguishing. We then consider the classification of all quotients of the maximally supersymmetric ten-dimensional plane wave under a spacelike iso… more
Date: November 24, 2003
Creator: Hubeny, Veronika E.; Rangamani, Mukund & Ross, Simon F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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How well do we know the electromagnetic form factors of the proton?

Description: Recent measurements of recoil polarization in elastic scattering have been used to extract the ratio of the electric to the magnetic proton form factors. These results disagree with Rosenbluth extractions from cross section measurements, indicating either an inconsistency between the two techniques, or a problem with either the polarization transfer or cross section measurements. To obtain precise knowledge of the proton form factors, they must first understand the source of this discrepancy.
Date: September 24, 2002
Creator: Arrington, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transition from Collisionless to Collisional MRI

Description: Recent calculations by Quataert et al. (2002) found that the growth rates of the magnetorotational instability (MRI) in a collisionless plasma can differ significantly from those calculated using MHD. This can be important in hot accretion flows around compact objects. In this paper, we study the transition from the collisionless kinetic regime to the collisional MHD regime, mapping out the dependence of the MRI growth rate on collisionality. A kinetic closure scheme for a magnetized plasma is … more
Date: July 24, 2003
Creator: Sharma, Prateek; Hammett, Gregory W. & Quataert, Eliot
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transverse expansion in <sup 197> Au + <sup 197> Au collisions at RHIC

Description: Using the RQMD model, transverse momentum distributions and particle ratios are studied for {sup 197}Au + {sup 197}Au collisions at {radical}s{sub NN} = 200 GeV. In particular, they present results on the mean transverse momentum of charged pions, charged kaons, protons and anti-protons and compare with experimental measurements. They discuss an approach to study early partonic collectivity in high energy nuclear collisions.
Date: June 24, 2003
Creator: Cheng, Y.; Liu, F.; Liu, K.; Schweda, K. & Xu, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low-Spin Collective Excitations in Deformed Nuclei: When is a B a B Vibration?

Description: The 0{sub 2}{sup +} level in deformed nuclei has historically been given the label {beta}, even though its properties vary drastically from one nucleus to another. By reviewing models from where the original term {beta} vibration arose, and appealing to microscopic calculations, guidelines are proposed for the properties of a true {beta} vibration. An examination of available data, including B(E2) values, {rho}{sup 2}(E0) values, and single- and two-nucleon-transfer populations, shows that very… more
Date: February 24, 2000
Creator: Garrett, P.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of Z{sup 0} to Heavy-quark couplings at SLD

Description: We present measurements of Z{sup 0} to heavy-quark coupling electroweak parameters, R{sub b}, R{sub c}, and parity-violation parameter A{sub c}, from SLD. The measurements are based on approximately 550k hadronic Z{sup 0} events collected in 1993-98. Obtained preliminary results of R{sub b} and R{sub c} measurements are R{sub b} = 0.2159 {+-} 0.0014 {+-} 0.0014 and R{sub c} = 0.1685 {+-} 0.0047 {+-} 0.0043. In the A{sub c} measurement, we use four methods to determine the initial-quark charge: … more
Date: May 24, 1999
Creator: Iwasaki, Masako
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electronuclear Division Annual Progress Report for Period Ending December 31, 1962

Description: Heavy-ion reactions in the low-Z region were investigated with 27-Mev nitrogen ions from the 73-inch Cyclotron and with 30-Mev oxygen ions from the Tandem Van de Graaff. Experiments included studies of angular distributions and excitation functions for transfer reactions, compound-nucleus reactions, effects of angular momentum on the density of nuclear states, and so-called Ericson fluctuations in the compound nucleus Si/sup 28/. Nuclear reactions induced with 22-Mev protons in the 86-Inch Cycl… more
Date: May 24, 1963
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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