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Issues for trigger processing at high luminosity colliders

Description: A number of issues for the design of trigger processors at future high-luminosity, high-energy colliders such as the Superconducting Super Collider and the Large Hadron Collider are discussed.
Date: November 1, 1989
Creator: Lankford, A.J.
Partner: UNT Libraries Government Documents Department
open access

High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice

Description: The number of emitted photons that can be obtained from a fluorophore increases with the incident light intensity and the duration of illumination. However, saturation of the absorption transition and photodestruction place natural limits on the ultimate signal-to-noise ratio that can be obtained. Equations have been derived to describe the fluorescence-to-background-noise ratio in the presence of saturating light intensities and photodestruction. The fluorescence lifetime and the photodestruct… more
Date: 1989
Creator: Mathies, R. A.; Peck, K. & Stryer, L.
Partner: UNT Libraries Government Documents Department
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Development of a mathematical model of a packed column for benzene removal from salt solutions

Description: A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other l… more
Date: January 1, 1989
Creator: Georgeton, G.K.
Partner: UNT Libraries Government Documents Department
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The U5. 0 undulator design for the advanced light source at LBL

Description: The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5 cm period, 5 m length with a 0.837 T maximum field at a 14 mm gap. A hybrid configuration utilizing Nd-Fe-B permanent magnet material and Vanadium Permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Ver… more
Date: August 1, 1989
Creator: Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B. et al.
Partner: UNT Libraries Government Documents Department
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Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system

Description: The goal of Hadron Spectroscopy is to find the spectrum of states formed by color singlet arrangements of quarks and gluons. Ideally these spectral states are associated with poles of the scattering matrix of hadrons which are the decay channels of the states. For example the {rho} meson is the lowest q{bar q} s-wave, spin one color singlet state and decays into {pi}{sup +}{pi}{sup -}. Since the {rho}decays in a relative p-wave, one finds the {rho} pole in the I = 1 p-wave {pi}{pi} phase shifts… more
Date: November 16, 1989
Creator: Longacre, R. S.
Partner: UNT Libraries Government Documents Department
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Transverse spin observables in chromodynamics

Description: Quantum Chromodynamics confronts a harsh series of tests in the attempt to formulate a comprehensive approach to the calculation of transverse spin observables. The basic obstacles to understanding transverse spin can be illustrated by considering the transverse structure function g{sub T}(x, Q{sup 2}) = g{sub 1}(x, Q{sup 2}) + g{sub 2}(x, Q{sup 2}), extracted from deep-inelastic scattering using a polarized lepton and a polarized proton. The inadequacy of the transverse-spin basis for quarks a… more
Date: December 1, 1989
Creator: Sivers, D.
Partner: UNT Libraries Government Documents Department
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Performance of a coincidence based blood activity monitor

Description: A new device has been constructed that measures the positron emitting radio-tracer concentration in arterial blood by extracting blood with a peristaltic pump, then measuring the activity concentration by detecting coincident pairs of 511 keV photons with a pair of heavy inorganic scintillators attached to photomultiplier tubes. The sensitivity of this device is experimentally determined to be 610 counts/second per {mu}Ci/ml, and has a paralyzing dead time of 1.2 {mu}s, so is capable of measuri… more
Date: December 1, 1989
Creator: Moses, W. W.
Partner: UNT Libraries Government Documents Department
open access

The Advanced Neutron Source

Description: The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 9{center dot}10{sup 19} m{sup -2}{center dot}s{sup -1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research. 5 refs., 5 figs.
Date: January 1, 1989
Creator: Hayter, J. B.
Partner: UNT Libraries Government Documents Department
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Enhanced tritium transport and release by solids modification

Description: To improve the tritium release characteristics of lithium ceramics, we are investigating the effects of dopants on tritium transport and release. Prior work has suggested a correlation between tritium and lithium diffusion in lithium-containing ceramics. This correlation has led us to propose a mechanism for tritium diffusion in which the tritium diffuses in the form of a lithium vacancy-triton complex. If this is the case, one should be able to increase the tritium diffusivity by increasing th… more
Date: January 1, 1989
Creator: Kopasz, J. P.; Tam, S. W. & Johnson, C. E.
Partner: UNT Libraries Government Documents Department
open access

State of the art in semiconductor detectors

Description: The state of the art in semiconductor detectors for elementary particle physics and x-ray astronomy is briefly reviewed. Semiconductor detectors are divided into two groups; classical semiconductor diode detectors; and semiconductor memory detectors. Principles of signal formation for both groups of detectors are described and their performance is compared. New developments of silicon detectors are reported here. 13 refs., 8 figs.
Date: January 1, 1989
Creator: Rehak, P. (Brookhaven National Lab., Upton, NY (USA)) & Gatti, E. (Politecnico di Milano, Milan (Italy))
Partner: UNT Libraries Government Documents Department
open access

Quarks and gluons in hadrons and nuclei

Description: These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of th… more
Date: December 1, 1989
Creator: Close, F. E.
Partner: UNT Libraries Government Documents Department
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Measuring the mass and width of the Z sup 0 : The status of the energy spectrometers

Description: The Stanford Linear Collider (SLC) located at the Stanford Linear Accelerator Center (SLAC) collides electrons and positrons produced in the linear accelerator pulse by pulse. The object is to produce collisions energetic enough to produce the heavy intermediate vector boson, the Z{sup 0}. An essential component of the SLC physics program is the precise knowledge of the center-of-mass energy of each interaction. We measure the energy of each collision by using two energy spectrometers. The spec… more
Date: May 1, 1989
Creator: Rouse, F.; Levi, M. (Lawrence Berkeley Lab., CA (United States)); Kent, J.; King, M.; Von Zanthier, C.; Watson, S. (California Univ., Santa Cruz, CA (United States)) et al.
Partner: UNT Libraries Government Documents Department
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Northern Arizona Basin Study (NABS), 1989

Description: An experiment was conducted to better understand a frequent layer of northwest winds found in the Northern Arizona region. This layer has been observed most often in winter near the surface at Page, Arizona, and often opposes larger scale upper level west winds. The results of this experiment improved both the temporal and the down-valley spatial resolution of the flow structure in this region during winter. 11 refs., 9 figs.
Date: January 1, 1989
Creator: Porch, W.M.; Clements, W.E. & Grant, T.A.
Partner: UNT Libraries Government Documents Department
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Hadron-hadron physics at high energy and luminosity

Description: I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date: November 8, 1989
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
open access

The particle-nuclear interface

Description: This paper discusses the differences and similarities between modern nuclear physics and particle physics. Similarities are presented between QED and QCD. (LSP)
Date: January 1, 1989
Creator: Close, F. E.
Partner: UNT Libraries Government Documents Department
open access

Examples of robots and teleoperators at the Savannah River Site

Description: The Savannah River Site manufactures nuclear materials for the US Department of Energy. In recent years robots and mobile teleoperators have been used to reduce the radiation exposure of personnel at this site. Two examples of robots that have significantly reduced radiation exposure are the Shielded Cells Waste Handling Robot and the Shielded Cells Sample Handling Robot. The Shielded Cells Waste Handling Robot has been in operation for over four years. It removes cans of radioactive waste from… more
Date: January 1, 1989
Creator: Ward, C. R.; Heckendorn, F. M. & Vandewalle, R. C.
Partner: UNT Libraries Government Documents Department
open access

The GALLEX Project

Description: The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of de… more
Date: January 1, 1989
Creator: Kirsten, T. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.))
Partner: UNT Libraries Government Documents Department
open access

VUV (vacuum ultraviolet) laser diagnostics of H sup - ion sources

Description: Vacuum ultraviolet laser absorption spectroscopy has been employed to measure the populations and temperatures of ground electronic state H-atoms and vibrationally-excited H{sub 2} molecules in a volume H{sup -} ion source. Measurements of both species have been made under a variety of discharge conditions. Vibrational levels to v{double prime}=8 have been measured, with the vibrational population distribution well described by a temperature of 4150K. 10 refs., 9 figs.
Date: November 1, 1989
Creator: Young, A. T.; Stutzin, G. C.; Leung, K. N. & Kunkel, W. B.
Partner: UNT Libraries Government Documents Department
open access

Some frontiers of accelerator physics

Description: This paper discusses some concepts of future accelerators such as free electron lasers, two beam accelerator; and plasma-based adiabatic compressor. 12 refs., 10 figs., 5 tabs. (LSP)
Date: October 13, 1989
Creator: Sessler, A. M.
Partner: UNT Libraries Government Documents Department
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Measurement of B sup 0 -- B sup 0 Mixing Using the MARK II at PEP

Description: B{sup 0}{bar B}{sup 0} mixing has been observed now by several experiments. The signature is the observation of an excess of same-sign dilepton events in datasets containing semileptonic B decays. Several years ago the MARK II published an upper limit on B{sup 0}{bar B}{sup 0} mixing at E{sub cm} = 29 GeV, using data taken at the e{sup +}e{sup {minus}} storage ring PEP. Here we report on the results of a new analysis with increased statistics, using refined methods with better sensitivity and c… more
Date: December 1, 1989
Creator: Porter, F.
Partner: UNT Libraries Government Documents Department
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Observation of tilt asymmetries in field-reversed configurations

Description: In recent years, part of the experimental effort on the FRX-C/LSM device has been devoted to understanding why good FRC confinement is observed only in a narrow window of the operating parameter space (fill pressures less than 5 mtorr and bias fields less than 0.8--0.9 kG). The transition from good to bad confinement has been shown for some time to correlate with strong axial shocks, suggesting a formation or stability problem. More recently, FRC magnetic asymmetries have been observed whenever… more
Date: January 1, 1989
Creator: Tuszewski, M.; Barnes, D. C.; Klingner, P. & Ng, Chun
Partner: UNT Libraries Government Documents Department
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Modeling of coupled geochemical and transport processes: An overview

Description: Early coupled models associated with fluid flow and solute transport have been limited by assumed conditions of constant temperature, fully saturated fluid flow, and constant pore fluid velocity. Developments including coupling of chemical reactions to variable fields of temperature and fluid flow have generated new requirements for experimental data. As the capabilities of coupled models expand, needs are created for experimental data to be used for both input and validation. 25 refs.
Date: October 1, 1989
Creator: Carnahan, C.L.
Partner: UNT Libraries Government Documents Department
open access

Uncertainty in the power distribution for a fast reactor burnup cycle

Description: Demonstration that advanced reactor designs satisfy safety and performance goals requires the analysis of uncertainties in calculated reactor characteristics. Two of the important performance characteristics of advanced liquid metal reactors (LMR) are the burnup reactivity swing and the local power peaking factor. Previous work reported a study of the uncertainty in the burnup reactivity swing attributable to nuclear data uncertainties for a typical advanced LMR design. The results are reported… more
Date: January 1, 1989
Creator: Downar, D.J.; Khalil, H. (Purdue Univ., Lafayette, IN (USA) & Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department
open access

JACEE long duration balloon flights

Description: JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs.
Date: January 1, 1989
Creator: Burnett, T.; Iwai, J.; Lord, J.J.; Strausz, S.; Wilkes, R.J. (Washington Univ., Seattle, WA (USA)); Dake, S. et al.
Partner: UNT Libraries Government Documents Department
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