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Measurement of energy deposited by charged-particle beams in composite targets

Description: We have measured the energy deposited in two types of composite targets by a number of charged-particle beams: targets made of /sup 238/U, Lucite, and polyethylene were exposed to 0.26-GeV protons and 0.33-GeV deuterons, and aluminum-Lucite composites were exposed to 0.5-GeV electrons. In addition, we measured neutrons and gamma rays emitted from solid targets of various materials (including /sup 238/U and iron) exposed to 0.26-GeV protons and 0.33-GeV deuterons. We used passive detectors (ther… more
Date: July 2, 1980
Creator: Farley, E.; Becker, J.; Crase, K.; Howe, R. & Selway, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of oxygen on and in beryllium using 2 MeV helium ions

Description: Analysis of oxygen on beryllium can be routinely performed using helium-ion backscattering (RBS). However, determination of the bulk oxygen concentration by this technique is limited to about 350 atomic parts per million (appM). We have performed simultaneous RBS and particle-induced x-ray emission (PIXE) measurements to improve the detection limit for bulk oxygen. The RBS measurements allowed determination of the surface oxygen before and after in-situ sputter cleaning by argon ions in an ultr… more
Date: October 2, 1986
Creator: Musket, R.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Weak interaction effects in e/sup +/e/sup -/ annihilation with polarised beams

Description: Although the standard gauge model of weak and electromagnetic interactions based on the work of Salam and Weinberg has met with great success, there are experimental facts that will require its extension or its modification to a new gauge model; the discovery of a heavy lepton at SLAC and the absence of parity violation in atoms that is expected from the neutral weak current coupling to electrons are discussed. Three tests are proposed that bear on these questions. First, heavy lepton productio… more
Date: November 2, 1977
Creator: Simard, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dissociative recombination of interstellar ions: electronic structure calculations for HCO/sup +/

Description: The present study of the interstellar formyl ion HCO/sup +/ is the first attempt to investigate dissociative recombination for a triatomic molecular ion using an entirely theoretical approach. We describe a number of fairly extensive electronic structure calculations that were performed to determine the reaction mechanism of the e-HCO/sup +/ process. Similar calculations for the isoelectronic ions HOC/sup +/ and HN/sub 2//sup +/ are in progress. 60 refs.
Date: July 2, 1985
Creator: Kraemer, W.P. & Hazi, A.U.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HOTSPUR progress report: neutron source spectrum characterization, and /sup 6/Li(n,x. cap alpha. ) and /sup 7/Li(n,x. cap alpha. ) cross section determination

Description: As a prerequisite to high accuracy measurements involving the bulk configuration of /sup 6/LiD we must have a good grasp of the details of the RTNS-I neutron source energy spectrum. Experiments to this end involving neutron yield vs deuteron energy, ratios of foil activation of selected elements, and pulse height distributions of a Si surface barrier detector are described. With this knowledge, the /sup 4/He-production cross sections for /sup 6/Li and /sup 7/Li are found experimentally to be 0.… more
Date: April 2, 1984
Creator: Goldberg, E. & Haight, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proposed LLNL electron beam ion trap

Description: The interaction of energetic electrons with highly charged ions is of great importance to several research fields such as astrophysics, laser fusion and magnetic fusion. In spite of this importance there are almost no measurements of electron interaction cross sections for ions more than a few times ionized. To address this problem an electron beam ion trap (EBIT) is being developed at LLNL. The device is essentially an EBIS except that it is not intended as a source of extracted ions. Instead … more
Date: July 2, 1985
Creator: Marrs, R.E.; Egan, P.O.; Proctor, I.; Levine, M.A.; Hansen, L.; Kajiyama, Y. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Topics in particle physics and cosmology

Description: The Standard Model of particle physics, together with the Big Bang model of the early universe, constitute a framework which encompasses our current understanding of fundamental laws and beginning of our universe. Despite recent speculative trends, quantum field theory remains the theoretical tool of choice for investigating new physics either at high energy colliders, or in the early universe. In this dissertation, several field theoretic phenomena relevant to cosmology or particle physics are… more
Date: August 2, 1991
Creator: Hsu, S.D.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Core-Particle Model for Periodically Focused Ion Beams with Intense Space-Charge

Description: A core-particle model is derived to analyze transverse orbits of test particles evolving in the presence of a core ion beam described by the KV distribution. The core beam has uniform density within an elliptical cross-section and can be applied to model both quadrupole and solenoidal focused beams in periodic or aperiodic lattices. Efficient analytical descriptions of electrostatic space-charge fields external to the beam core are derived to simplify model equations. Image charge effects are a… more
Date: August 2, 2006
Creator: Lund, S M; Barnard, J J; Bukh, B; Chawla, S R & Chilton, S H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vector Unparticle Contributions to Lepton g-2

Description: The generic unparticle propagator may be modified in two ways. Breaking the conformal symmetry effectively adds a mass term to the propagator, while considering vacuum polarization corrections adds a width-like term. Both of these modifications result naturally from the coupling of the unparticle to standard model (SM) fields. We explore how these modifications to the propagator affect the calculation of the lepton anomalous magnetic moment using an integral approximation of the propagator that… more
Date: February 2, 2009
Creator: Conley, John A. & Gainer, James S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Introduction to Electroweak Symmetry Breaking

Description: The Standard Model (SM) is the backbone of elementary particle physics-not only does it provide a consistent framework for studying the interactions of quark and leptons, but it also gives predictions which have been extensively tested experimentally. In these notes, I review the electroweak sector of the Standard Model, discuss the calculation of electroweak radiative corrections to observables, and summarize the status of SM Higgs boson searches. Despite the impressive experimental successes,… more
Date: October 2, 2008
Creator: Dawson,S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sorting chromatic sextupoles for easily and effectively correcting second order chromaticity in the Relativistic Heavy Ion Collider

Description: Based on the contributions of the chromatic sextupole families to the half-integer resonance driving terms, we discuss how to sort the chromatic sextupoles in the arcs of the Relativistic Heavy Ion Collider (RHIC) to easily and effectively correct the second order chromaticities. We propose a method with 4 knobs corresponding to 4 pairs of chromatic sextupole families to online correct the second order chromaticities. Numerical simulation justifies this method, showing that this method reduces … more
Date: January 2, 2009
Creator: Luo, Y.; Tepikian, S.; Fischer, W.; Robert-Demolaize, G. & Trbojevic, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamic aperture evaluation of the proposed lattices for the RHIC 2009 polarized proton run

Description: In the article we evaluate the dynamic apertures of the proposed lattices for the coming Relativistic Heavy Ion Collider (RHIC) 2009 polarized proton (pp) 100 GeV and 250 GeV runs. One goal of this study is to find out the appropriate {beta}* for the coming 2009 pp runs. Another goal is to study the effect of second order chromaticity correction in the RHIC pp runs.
Date: January 2, 2009
Creator: Luo, Y.; Bai, M.; Beebe-Wang, J.; Fischer, W.; Montag, C.; Robert-Demolaize, G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Angular Distributions in the Decays B to K*l+l-

Description: The authors use a sample of 384 million B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider to study angular distributions in the rare decays B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -}. For low dilepton invariant masses, m{sub {ell}{ell}} < 2.5 GeV/c{sup 2}, they measure a lepton forward-backward asymmetry {Alpha}{sub FB} = 0.24{sub -0.23}{sup +0.18} {+-} 0.05 and K* longitud… more
Date: May 2, 2008
Creator: Collaboration, The BABAR & Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Hard X-ray View on Two Distant VHE Blazars: 1ES 1101-232 and 1ES 1553+113

Description: TeV-blazars are known as prominent non-thermal emitters across the entire electromagnetic spectrum with their photon power peaking in the X-ray and TeV-band. If distant, absorption of -ray photons by the extragalactic background light (EBL) alters the intrinsic TeV spectral shape, thereby affecting the overall interpretation. Suzaku observations for two of the more distant TeV-blazars known to date, 1ES 1101-232 and 1ES 1553+113, were carried out in May and July 2006, respectively, including a … more
Date: May 2, 2008
Creator: Reimer, A.; Costamente, L.; /Stanford U., HEPL /KIPAC, Menlo Park; Madejski, G.; /KIPAC, Menlo Park /SLAC; Reimer, O. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of Booster Scraping in Polarized Proton Runs 2006 and 2008

Description: Effects of the Booster vertical scraping on the RHIC beam polarization, the RHIC beam emittance, and on the Booster to AGS transfer efficiency and AGS transmission as well, are further studied. In [1], the strong dependence of the RHIC beam polarization and emittance on bunch intensity in proton run 2008 (pp08) is compared with the proton run 2006 (pp06), where the dependence is much weaker. The setting in the AGS Booster, mainly the vertical scraping, is suspected to having played a role in th… more
Date: January 2, 2009
Creator: Zhang, S. Y.; Ahrens, L.; Huang, H. & Zeno, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons

Description: The authors report measurements of branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup -}, {pi}{sup 0}, {eta} and {eta}{prime}, based on 348 fb{sup -1} of data collected with the BABAR detector, using B{sup 0} and B{sup +} mesons found in the recoil of a second B meson decaying as B {yields} D{sup (*)}{ell}{nu}{sub {ell}}. Assuming isospin symmetry, they combine pionic branching fractions to obtain {Beta}(B{sup 0} {yields} … more
Date: June 2, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of the Noncommutative Standard Model in WW Scattering

Description: We examine W pair production in the Noncommutative Standard Model constructed with the Seiberg-Witten map. Consideration of partial wave unitarity in the reactions WW {yields} WW and e{sup +}e{sup -} {yields} WW shows that the latter process is more sensitive and that tree-level unitarity is violated when scattering energies are of order a TeV and the noncommutative scale is below about a TeV. We find that WW production at the LHC is not sensitive to scales above the unitarity bounds. WW produc… more
Date: December 2, 2008
Creator: Conley, John A. & Hewett, JoAnne L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Superconducting Storage Cavity for RHIC

Description: This document provides a top-level description of a superconducting cavity designed to store hadron beams in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It refers to more detailed documents covering the various issues in designing, constructing and operating this cavity. The superconducting storage cavity is designed to operate at a harmonic of the bunch frequency of RHIC at a relatively low frequency of 56 MHz. The current storage cavities of RHIC operate at 1… more
Date: January 2, 2009
Creator: Ben-Zvi, Ilan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quark--parton model with large parton k/sub T/

Description: The quark--parton model is generalized to allow for arbitrarily large parton k/sub T/. Since it is expected that < k/sub T/ > will rise with Q/sup 2/ in (highly virtual) photon mediated processes, this generalization is necessary to restore the applicability of the quark-parton model. By treating k/sub T/ as an essential kinematical variable, the introduction of a new scaling variable z is considered. Together with Bjorken's x variable, a unified kinematical description is given of the four dis… more
Date: February 2, 1978
Creator: Hwa, R.C.; Matsuda, S. & Roberts, R.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dependence of indoor-pollutant concentrations on sources, ventilation rates, and other removal factors

Description: The behavior of several classes of chemical and physical pollutants include emissions from combustion appliances, radon and its progeny, formaldehyde, and other organic compounds. Current research at Lawrence Berkeley Laboratory is described and research needs in the area of indoor air quality is pointed out. (ACR)
Date: August 2, 1983
Creator: Nero, A. V. Jr. & Grimsrud, D. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lawrence Livermore Laboratory Geothermal Energy Program. A Status Report on the Development of the Total-Flow Concept

Description: The technology development activities of the Geothermal Energy Program at the Lawrence Livermore Laboratory are summarized. Significant progress toward development of the Total-Flow concept was made during FY 1978. The results show that the original goal of 70% engine efficiency for the Total-Flow impulse turbine is achievable, that a Total-Flow system is competitive economically with conventional systems, and that the Total-Flow concept offers the benefit of more efficient utilization of geoth… more
Date: October 2, 1978
Creator: Austin, A. L. & Lundberg, A. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wavelengths of the 3p-3d transitions of the Co- and Fe-like ions: The effects of electron correlation

Description: The experimental observations of the 3p/sup 6/ 3d/sup 9/ /sup 2/D - 3p/sup 5/ 3d/sup 10/ /sup 2/p transitions of the Co-like ions and 3p/sup 6/ 3d/sup 8/ /sup 3/F/sub 4/ - 3p/sup 5/ 3d/sup 9/ /sup 3/F/sub 3/ of the Fe-like ions have recently been extended to highly charged ions of heavy elements up to uranium (Z = 92). A comparison between the observed energies and calculated values from the Dirac-Fock model indicated persistent discrepancies of 3 to 4 eV for all ions. Systematic multiconfigura… more
Date: September 2, 1987
Creator: Chen, Mau Hsiung
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optical and thermal energy discharge from tritiated solid hydrogen

Description: The authors are investigating mechanisms of energy storage and release in tritiated solid hydrogens, by a variety of techniques including ESR, NMR and thermal and optical emission. The nuclear decay of a triton in solid hydrogen initiates the conversion of nuclear energy into stored chemical energy by producing unpaired hydrogen atoms which are trapped within the molecular lattice. The ability to store large quantities of atoms in this manner has been demonstrated and can serve as a basis for n… more
Date: April 2, 1991
Creator: Magnotta, F.; Mapoles, E. R.; Collins, G. W. & Souers, P. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SEM (Scanning Electron Microscopy) Analysis of Rock Varnish Chemistry for Cation-Ratio Dating: An Examination of Electron Beam Penetration Depths

Description: Rock varnish is a microns-thick manganese- and iron-rich coating that forms on exposed rock surfaces in arid and semi-arid environments. Empirical correlations of the varnish cation ratio (K+Ca)/Ti with age have been used to estimate ages of geomorphic surfaces, with varnish chemistry generally acquired by either proton-induced x-ray emission (PIXE) analysis of natural varnish surfaces. Chemical analyses of rock varnish with SEM/EDX utilize a sequence of accelerating voltages to vary penetratio… more
Date: April 2, 1990
Creator: Reneau, Steven L.; Raymond, Robert Jr.; Harrington, Charles D. & Hagan, Roland C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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