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Medium-energy nuclear physics research. Final technical progress report, May 1, 1971-November 30, 1981

Description: Final results are summarized for this program with the primary emphasis on measurement of ten independent parameters for proton-proton elastic scattering at 800 MeV and four independent such parameters at 650 MeV. Inelastic proton-proton reactions have also been measured at 800 MeV. Proton-deuteron elastic scattering cross sections and polarization analyzing powers have been obtained at 800 MeV. Proton-nucleus total and total reaction cross sections were measured at 700 MeV for a number of nucl… more
Date: November 30, 1981
Creator: Willard, H.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Frustrated spin correlations in diluted spin ice Ho2-xLaxTi2O7

Description: We have studied the evolution of the structural properties as well as the static and dynamic spin correlations of spin ice Ho2Ti2O7, where Ho was partially replaced by non-magnetic La. The crystal structure of diluted samples Ho2-xLaxTi2O7 was characterized by x-ray and neutron diffraction and by Ho L-III-edge and Ti K-edge extended x-ray absorption fine structure (EXAFS) measurements. It is found that the pyrochlore structure remains intact until about x = 0.3, but a systematic increase in loc… more
Date: April 30, 2008
Creator: Ehlers, Georg; Ehlers, G.; Mamontov, E.; Zamponi, M.; Faraone, A.; Qiu, Y. et al.
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Partner: UNT Libraries Government Documents Department
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Topological Symmetry, Spin Liquids and CFT Duals of Polyakov Model with Massless Fermions

Description: We prove the absence of a mass gap and confinement in the Polyakov model with massless complex fermions in any representation of the gauge group. A U(1){sub *} topological shift symmetry protects the masslessness of one dual photon. This symmetry emerges in the IR as a consequence of the Callias index theorem and abelian duality. For matter in the fundamental representation, the infrared limits of this class of theories interpolate between weakly and strongly coupled conformal field theory (CFT… more
Date: April 30, 2008
Creator: Unsal, Mithat
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exploring nanomagnetism with soft x-ray microscopy

Description: Magnetic soft X-ray microscopy images magnetism in nanoscale systems with a spatial resolution down to 15nm provided by state-of-the-art Fresnel zone plate optics. X-ray magnetic circular dichroism (X-MCD) is used as element-specific magnetic contrast mechanism similar to photoemission electron microscopy (PEEM), however, with volume sensitivity and the ability to record the images in varying applied magnetic fields which allows to study magnetization reversal processes at fundamental length sc… more
Date: October 30, 2006
Creator: Fischer, P.; Kim, D. H.; Mesler, B. L.; Chao, W.; Sakdinawat,A. E. & Anderson, E. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Breathing Orbital Valence Bond Method in Diffusion Monte Carlo: C-H Bond Dissociation ofAcetylene

Description: This study explores the use of breathing orbital valence bond (BOVB) trial wave functions for diffusion Monte Carlo (DMC). The approach is applied to the computation of the carbon-hydrogen (C-H) bond dissociation energy (BDE) of acetylene. DMC with BOVB trial wave functions yields a C-H BDE of 132.4 {+-} 0.9 kcal/mol, which is in excellent accord with the recommended experimental value of 132.8 {+-} 0.7 kcal/mol. These values are to be compared with DMC results obtained with single determinant … more
Date: May 30, 2008
Creator: Domin, D.; Braida, Benoit & Lester Jr., William A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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PKU-RBRC Workshop on Transverse Spin

Description: Understanding the structure of the nucleon is a fundamental question in subatomic physics, and it has been under intensive investigation for the last several years. Modern research focuses in particular on the spin structure of the nucleon. Experimental and theoretical investigations worldwide over the last few decades have established that, contrary to nave quark model expectations, quarks carry only about 30% of the totd spin of the proton. The origin of the remaining spin is the key question… more
Date: June 30, 2008
Creator: Avakian,H.; Bunce, G. & Yuan, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Charmonium spectroscopy, 1987

Description: The state of charmonium spectroscopy is reviewed. All analyses proceed from a spin-dependent, non-relativistic Schroedinger equation. Many of the possible branching ratios for charm like states are investigated. 17 refs.
Date: July 30, 1987
Creator: Cahn, R.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin structure functions of the nucleon at low Q{sup 2} and {nu}

Description: Phenomenological approaches to describe the spin structure functions an spin sum rules for proton and neutrons at low momentum transfer Q{sup 2} and energy transfer {nu}, i.e. in the region of the nucleon resonances are discussed. Experiments to measure A{sub 1}{sup p}, A{sub 2}{sup p} and N{sub 1}{sup n} structure functions at CEBAF in a Q{sup 2} range from 0.15 to 2.0 GeV{sup 2}, and a W range from threshold to 2.2 GeV are presented.
Date: June 30, 1993
Creator: Burkert, V. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of the spin-flip time in ferromagnetic SrRuO3 from time-resolved Kerr measurements

Description: We report time-resolved Kerr effect measurements of magnetization dynamics in ferromagnetic SrRuO{sub 3}. We observe that the demagnetization time slows substantially at temperatures within 15K of the Curie temperature, which is {approx} 150K. We analyze the data with a phenomenological model that relates the demagnetization time to the spin flip time. In agreement with our observations the model yields a demagnetization time that is inversely proportional to T-T{sub c}. We also make a direct c… more
Date: July 30, 2010
Creator: Kantner, C. L. S.; Langner, M. C.; Siemons, W.; Blok, J. L.; Koster, G.; Rijnders, A.J. H. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gluons and the quark sea at high energies: distributions, polarization, tomography

Description: This report is based on a ten-week program on Gluons and the quark sea at high-energies, which took place at the Institute for Nuclear Theory (INT) in Seattle in Fall 2010. The principal aim of the program was to develop and sharpen the science case for an Electron-Ion Collider (EIC), a facility that will be able to collide electrons and positrons with polarized protons and with light to heavy nuclei at high energies, offering unprecedented possibilities for in-depth studies of quantum chromody… more
Date: September 30, 2011
Creator: Boer, D.; Venugopalan, R.; Diehl, M.; Milner, R.; Vogelsang, W. & al., et
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a High Pressure/High Temperature Down-hole Turbine Generator

Description: As oil & natural gas deposits become more difficult to obtain by conventional means, wells must extend to deeper more heat-intensive environments. The technology of the drilling equipment required to reach these depths has exceeded the availability of electrical power sources needed to operate these tools. Historically, logging while drilling (LWD) and measure while drilling (MWD) devices utilized a wireline to supply power and communication from the operator to the tool. Lithium ion batteries … more
Date: June 30, 2008
Creator: Plamp, Ben
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Participation of Glutamate-354 of the CP43 Polypeptide in the Ligation of Mn and the Binding of Substrate Water in Photosystem II

Description: In the current X-ray crystallographic structural models of photosystem II, Glu354 of the CP43 polypeptide is the only amino acid ligand of the oxygen-evolving Mn4Ca cluster that is not provided by the D1 polypeptide. To further explore the influence of this structurally unique residue on the properties of the Mn4Ca cluster, the CP43-E354Q mutant of the cyanobacterium Synechocystis sp. PCC 6803 was characterized with a variety of biophysical and spectroscopic methods, including polarography, EPR… more
Date: September 30, 2010
Creator: Service, Rachel; Yano, Junko; McConnell, Iain; Hwang, Hong Jin; Niks, Dimitri; Hille, Russ et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin Echo and Interference in Synchrotrons

Description: Spin dynamics in crossing a single depolarization resonance is a well-studied subject. One well-known example is that of Froissart and Stora in 1960. More is needed to complete the understanding, particularly of the transient effects, when crossing a single resonance, but question arises what happens if we cross two resonances or cross a single resonance twice. When a resonance is crossed twice, the particle's spin dynamics encounters two additional phenomena. First, the two crossings will inte… more
Date: November 30, 2006
Creator: Chao, Alex
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resolving the Formation of Protogalaxies. III.Feedback from the First Stars

Description: The first stars form in dark matter halos of masses {approx}10{sup 6}M{sub {circle_dot}} as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from their shallow potential well of their surrounding dark matter halos. We use cosmological adaptive mesh refinement simulations that include self-consistent Population III star formation and feedback to examine the properties of assembling early dwarf galaxies. Accurate radiative tran… more
Date: October 30, 2007
Creator: Wise, John H.; Abel, Tom & /KIPAC, Menlo Park
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Implementation of the Polarized HD target at the Thomas Jefferson National Accelerator Facility

Description: The original goal of this proposal was to study frozen spin polarized targets (HD target and other technologies) and produce a conceptual design report for the implementation of such a target in the HALL B detector of the Thomas Jefferson National Accelerator Facility (JLab). During the first two years of the proposal, we came to the conclusion that the best suited target for JLab was a frozen spin target and helped with the design of such a target. We have not only achieved our original goal b… more
Date: January 30, 2007
Creator: Djalali, Chaden & Tedeschi, David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Combined local-density and dynamical mean field theory calculations for the compressed lanthanides Ce, Pr, and Nd

Description: This paper reports calculations for compressed Ce (4f{sup 1}), Pr (4f{sup 2}), and Nd (4f{sup 3}) using a combination of the local-density approximation (LDA) and dynamical mean field theory (DMFT), or LDA+DMFT. The 4f moment, spectra, and the total energy among other properties are examined as functions of volume and atomic number for an assumed face-centered cubic (fcc) structure. These materials are seen to be strongly localized at ambient pressure and for compressions up through the experim… more
Date: March 30, 2005
Creator: McMahan, A. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hard Diffraction in QCD

Description: Gluon exchange between the outgoing quarks and the target spectators affects the structure functions measured in deep inelastic scattering in a profound way, leading to diffractive lepto-production processes, the shadowing and antishadowing of nuclear structure functions, and target spin asymmetries--leading-twist physics not incorporated in the light-front wavefunctions of the target computed in isolation. I also discuss the diffraction dissociation of hadrons into jets as a tool for resolving… more
Date: June 30, 2005
Creator: Brodsky, Stanley J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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EXCITATION OF STRUCTURAL RESONANCE DUE TO A BEARING FAILURE

Description: Vibration due to a bearing failure in a pump created significant vibrations in a fifteen foot by fifteen foot by eight feet tall mounting platform due to excitation of resonant frequencies. In this particular application, an 18,000 pound pump was mounted to a structural steel platform. When bearing damage commenced, the platform vibrated with sufficient magnitude that conversations could not be heard within forty feet of the pump. Vibration analysis determined that the frequency of the bearing … more
Date: April 30, 2007
Creator: Leishear, R & David Stefanko, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radio-Loudness of Active Galactic Nuclei: Observational Facts and Theoretical Implications

Description: We investigate how the total radio luminosity of AGN-powered radio sources depends on their accretion luminosity and the central black hole mass. Our studies cover about seven orders of magnitude in accretion luminosity (expressed in Eddington units, i.e. as Eddington ratios) and the full range of AGN black hole masses. We find that AGNs form two distinct and well separated sequences on the radio-loudness--Eddington-ratio plane. The ''upper'' sequence is formed by radio selected AGNs, the ''low… more
Date: January 30, 2007
Creator: Sikora, Marek; /Warsaw, Copernicus Astron. Ctr. /Paris, Inst. Astrophys.; Stawarz, Lukasz; /Heidelberg Observ. /Heidelberg, Max Planck Inst. /Jagiellonian U., Astron. Observ.; Lasota, Jean-Pierre & /Paris, Inst. Astrophys.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Next-to-Leading Order Calculation of the Single Transverse Spin Asymmetry in the Drell-Yan Process

Description: We calculate the next-to-leading order perturbative QCD corrections to the transverse momentum weighted single transverse spin asymmetry in Drell-Yan lepton pair production in hadronic collisions. We identify the splitting function relevant for the scale evolution of the twist-three quark-gluon correlation function. We comment on the consequences of our results for phenomenology.
Date: March 30, 2009
Creator: Vogelsang, Werner & Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin Properties of Transition-Metallorganic Self-Assembled Molecules

Description: This report summarizes SRI's accomplishments on the project, 'Spin Properties of Transition-Metallorganic Self-Assembled Molecules' funded by the Office of Basic Energy Sciences, US Department of Energy. We have successfully carried out all tasks identified in our proposal and gained significant knowledge and understanding of spin-polarized electronic structure, spin relaxation, and spin-dependent transport in transition-metallorganic molecules and enhohedral fullerenes. These molecules contain… more
Date: June 30, 2010
Creator: Yu, Zhi Gang
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photo-Induced Spin-State Conversion in Solvated Transition Metal Complexes Probed via Time-Resolved Soft X-ray Spectroscopy

Description: Solution-phase photoinduced low-spin to high-spin conversion in the FeII polypyridyl complex [Fe(tren(py)3)]2+ (where tren(py)3 is tris(2-pyridylmethyliminoethyl)amine) has been studied via picosecond soft X-ray spectroscopy. Following 1A1 --> 1MLCT (metal-to-ligand charge transfer) excitation at 560 nm, changes in the iron L2- and L3-edges were observed concomitant with formation of the transient high-spin 5T2 state. Charge-transfer multiplet calculations coupled with data acquired on low-s… more
Date: April 30, 2010
Creator: Huse, Nils; Kim, Tae Kyu; Jamula, Lindsey; McCusker, James K.; de Groot, Frank M. F. & Schoenlein, Robert W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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