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High gain free electron laser at ETA

Description: A single pass, tapered electron wiggler and associated beam transport has been constructed at the Experimental Test Accelerator (ETA) at Lawrence Livermore National Laboratory (LLNL). The system is designed to transport 1 kA of 4.5 MeV electrons with an emittance of 30 millirad-cm. The planar wiggler is provided by a pulsed electromagnet. The interaction region is an oversized rectangular waveguide. Quadrupole fields stabilize the beam in the plane parallel to the wiggler field. The 3 meter lon… more
Date: February 9, 1983
Creator: Orzechowski, T.J.; Prosnitz, D.; Halbach, K.; Kuenning, R.; Paul, A.; Hopkins, D. et al.
Partner: UNT Libraries Government Documents Department
open access

EUV multilayer coatings for the Atmospheric Imaging Assembly instrument aboard the Solar Dynamics Observatory

Description: Multilayer coatings for the 7 EUV channels of the AIA have been developed and completed successfully on all AIA flight mirrors. Mo/Si coatings (131, 171, 193.5, 211 {angstrom}) were deposited at Lawrence Livermore National Laboratory (LLNL). Mg/SiC (304, 335 {angstrom}) and Mo/Y (94 {angstrom}) coatings were deposited at Columbia University. EUV reflectance of the 131/335 {angstrom}, 171 {angstrom}, 193.5/211 {angstrom} primary and secondary flight mirrors and the 94/304 {angstrom} secondary fl… more
Date: February 9, 2006
Creator: Soufli, R.; Windt, D. L.; Robinson, J. C.; Baker, S. L.; Spiller, E.; Dollar, F. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Neutron and Photon Transport in Sea-Going Cargo Containers

Description: Factors affecting sensing of small quantities of fissionable material in large sea-going cargo containers by neutron interrogation and detection of {beta}-delayed photons are explored. The propagation of variable-energy neutrons in cargos, subsequent fission of hidden nuclear material and production of the {beta}-delayed photons, and the propagation of these photons to an external detector are considered explicitly. Detailed results of Monte Carlo simulations of these stages in representative c… more
Date: February 9, 2005
Creator: Pruet, J; Descalle, M; Hall, J; Pohl, B & Prussin, S G
Partner: UNT Libraries Government Documents Department
open access

FUEL CASK IMPACT LIMITER VULNERABILITIES

Description: Cylindrical fuel casks often have impact limiters surrounding just the ends of the cask shaft in a typical 'dumbbell' arrangement. The primary purpose of these impact limiters is to absorb energy to reduce loads on the cask structure during impacts associated with a severe accident. Impact limiters are also credited in many packages with protecting closure seals and maintaining lower peak temperatures during fire events. For this credit to be taken in safety analyses, the impact limiter attachm… more
Date: February 9, 2009
Creator: Leduc, D; Jeffery England, J & Roy Rothermel, R
Partner: UNT Libraries Government Documents Department
open access

Quark Matter 2006: High-pt and jets

Description: An overview of new experimental results on high-pT particleproduction and jets in heavy ion collisions from the Quark Matter 2006conference is presented.
Date: February 9, 2007
Creator: van Leeuwen, Marco
Partner: UNT Libraries Government Documents Department
open access

Magnetic mirror fusion research at the Lawrence Livermore Laboratory

Description: An overall view is given of progress and plans for pressing forward with mirror research at Livermore. No detail is given on any one subject, and many interesting investigations being carried out at University laboratories in the U.S. that augment and support efforts at Livermore are omitted.
Date: February 9, 1979
Creator: Post, Richard F.
Partner: UNT Libraries Government Documents Department
open access

High-temperature superconductor applications development at Argonne National Laboratory

Description: Developments at Argonne National Laboratory of near and intermediate term applications using high-temperature superconductors are discussed. Near-term applications of liquid-nitrogen depth sensors, current leads, and magnetic bearings are discussed in detail.
Date: February 9, 1992
Creator: Hull, J.R. & Poeppel, R.B.
Partner: UNT Libraries Government Documents Department
open access

ROOM: A recursive object oriented method for information systems development

Description: Although complementary for the development of complex systems, top-down structured design and object oriented approach are still opposed and not integrated. As the complexity of the systems are still growing, and the so-called software crisis still not solved, it is urgent to provide a framework mixing the two paradigms. This paper presents an elegant attempt in this direction through our Recursive Object-Oriented Method (ROOM) in which a top-down approach divides the complexity of the system a… more
Date: February 9, 1994
Creator: Thelliez, T. & Donahue, S.
Partner: UNT Libraries Government Documents Department
open access

High-temperature superconductor applications development at Argonne National Laboratory

Description: Developments at Argonne National Laboratory of near and intermediate term applications using high-temperature superconductors are discussed. Near-term applications of liquid-nitrogen depth sensors, current leads, and magnetic bearings are discussed in detail.
Date: February 9, 1992
Creator: Hull, J. R. & Poeppel, R. B.
Partner: UNT Libraries Government Documents Department
open access

Three-Dimensional Hydrodynamic Experiments on the National Ignition Facility

Description: The production of supersonic jets of material via the interaction of a strong shock wave with a spatially localized density perturbation is a common feature of inertial confinement fusion and astrophysics. The behavior of two-dimensional (2D) supersonic jets has previously been investigated in detail [J. M. Foster et. al, Phys. Plasmas 9, 2251 (2002)]. In three-dimensions (3D), however, there are new aspects to the behavior of supersonic jets in compressible media. In this paper, the commission… more
Date: February 9, 2005
Creator: Blue, B E; Robey, H F; Glendinning, S G; Bono, M J; Dixit, S N; Foster, J M et al.
Partner: UNT Libraries Government Documents Department
open access

The EGS4 Code System: Solution of gamma-ray and electron transport problems

Description: In this paper we present an overview of the EGS4 Code System -- a general purpose package for the Monte Carlo simulation of the transport of electrons and photons. During the last 10-15 years EGS has been widely used to design accelerators and detectors for high-energy physics. More recently the code has been found to be of tremendous use in medical radiation physics and dosimetry. The problem-solving capabilities of EGS4 will be demonstrated by means of a variety of practical examples. To faci… more
Date: February 9, 1990
Creator: Nelson, W. R. & Namito, Yoshihito.
Partner: UNT Libraries Government Documents Department
open access

PREPARING FOR A SUCCESSFUL EVMS CERTIFICATION

Description: The client, a government agency, requires its contractor to obtain an Earned Value Management System (EVMS) certification that meets the intent of ANSI/EIA-748-B, Earned Value Management Systems. The contractor has extensive experience with certification preparation, having completed two certifications within two years. Information from a previous EVMS certification and internal system surveillances are used to prepare for client-based EVMS certifications and bi-annual surveillances. The contra… more
Date: February 9, 2011
Creator: SL, CROWE & AD, BASCHE
Partner: UNT Libraries Government Documents Department
open access

Laser supported solid state absorption fronts in silica

Description: We develop a model based on simulation and experiment that explains the behavior of solid-state laser-supported absorption fronts generated in fused silica during high intensity (up to 5GW/cm{sup 2}) laser exposure. We find that the absorption front velocity is constant in time and is nearly linear in laser intensity. Further, this model can explain the dependence of laser damage site size on these parameters. This behavior is driven principally by the temperature-activated deep sub band-gap op… more
Date: February 9, 2010
Creator: Carr, C W & Bude, J D
Partner: UNT Libraries Government Documents Department
open access

Finding Regions of Interest on Toroidal Meshes

Description: Fusion promises to provide clean and safe energy, and a considerable amount of research effort is underway to turn this aspiration intoreality. This work focuses on a building block for analyzing data produced from the simulation of microturbulence in magnetic confinementfusion devices: the task of efficiently extracting regions of interest. Like many other simulations where a large amount of data are produced,the careful study of ``interesting'' parts of the data is critical to gain understand… more
Date: February 9, 2011
Creator: Wu, Kesheng; Sinha, Rishi R; Jones, Chad; Ethier, Stephane; Klasky, Scott; Ma, Kwan-Liu et al.
Partner: UNT Libraries Government Documents Department
open access

Amorphous clusters in Co implanted ZnO induced by boron pre-implantation

Description: We demonstrate the formation of superparamagnetic/ferromagnetic regions within ZnO(0001) single crystals sequently implanted with B and Co. While the pre-implantation with B plays a minor role for the electrical transport properties, its presence leads to the formation of amorphous phases. Moreover, B acts strongly reducing on the implanted Co. Thus, the origin of the ferromagnetic ordering in local clusters with large Co concentration is itinerant d-electrons as in the case of metallic Co. The… more
Date: February 9, 2009
Creator: Potzger, K.; Shalimov, A.; Zhou, S.; Schmidt, H.; Mucklich, A.; Helm, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Indications of Conical Emission of Charged Hadrons at the BNL Relativistic HeavyIon Collider

Description: Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d + Au, and Au + Au collisions at {radical}s{sub NN} = 200 GeV by the STAR experiment. Dijet structures are observed in pp, d + Au and peripheral Au + Au collisions. An additional structure is observed in central Au + Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be {theta} = 1.37 {+-} 0.02(stat){sub -0.07}{sup +0.06}… more
Date: February 9, 2009
Creator: STAR Collaboration
Partner: UNT Libraries Government Documents Department
open access

Spin Equilibria in Monomeric Manganocenes: Solid State Magnetic and EXAFS Studies

Description: Magnetic susceptibility measurements and X-ray data confirm that tert-butyl-substituted manganocenes [(Me{sub 3}C){sub n}C{sub 5}H{sub 5?n}]{sub 2}Mn (n = 1, 2) follow the trend previously observed with the methylated manganocenes; that is, electron-donating groups attached to the Cp ring stabilize the low-spin (LS) electronic ground state relative to Cp{sub 2}Mn and exhibit higher spin-crossover (SCO) temperatures. However, introducing three CMe{sub 3} groups on each ring gives a temperature-i… more
Date: February 9, 2009
Creator: Walter, M. D.; Sofield, C. D.; Booth, C. H. & Andersen, R. A.
Partner: UNT Libraries Government Documents Department
open access

Vacuum-Ultraviolet Photoionization and Mass Spectrometric Characterization of Lignin Monomers Coniferyl and Sinapyl Alcohols

Description: The fragmentation mechanisms of monolignols under various energetic processes are studied with jet-cooled thermal desorption molecular beam (TDMB) mass spectrometry (MS), 25 keV Bi3+ secondary ion MS (SIMS), synchrotron vacuum-ultraviolet secondary neutral MS (VUV-SNMS) and theoretical methods. Experimental and calculated appearance energies of fragments observed in TDMB MS indicate that the coniferyl alcohol photoionization mass spectra contain the molecular parent and several dissociative pho… more
Date: February 9, 2011
Creator: Takahashi, Lynelle K.; Zhou, Jia; Kostko, Oleg; Golan, Amir; Leone, Stephen R. & Ahmed, Musahid
Partner: UNT Libraries Government Documents Department
open access

Annual Growth Bands in Hymenaea courbaril

Description: One significant source of annual temperature and precipitation data arises from the regular annual secondary growth rings of trees. Several tropical tree species are observed to form regular growth bands that may or may not form annually. Such growth was observed in one stem disk of the tropical legume Hymenaea courbaril near the area of David, Panama. In comparison to annual reference {Delta}{sup 14}C values from wood and air, the {Delta}{sup 14}C values from the secondary growth rings formed … more
Date: February 9, 2004
Creator: Westbrook, J. A.; Guilderson, T. P. & Colinvaux, P. A.
Partner: UNT Libraries Government Documents Department
open access

The Effect of Diluent Gases In The Shock Tube and Rapid Compression Machine

Description: Studying the details of hydrocarbon chemistry in an internal combustion engine is not straightforward. A number of factors, including varying conditions of temperature and pressure, complex fluid motions, as well as variation in the composition of gasoline, render a meaningful characterization of the combusting system difficult. Some simplified experimental laboratory devices offer an alternative to complex engine environments: they remove some of the complexities that exist in real engines but… more
Date: February 9, 2007
Creator: Silke, E; W?rmel, J; O?Conaire, M; Simmie, J & Curran, H
Partner: UNT Libraries Government Documents Department
open access

Charm and Charmonium Spectroscopy From B-Factories

Description: New and recent results are presented on charm and charmonium spectroscopy from BABAR experiment at SLAC. In particular, measurements on D{sub sJ} states branching fractions have been performed both in B-decays and inclusive e{sup +}e{sup -} {yields} c{bar c} interactions. Here a search for D{sub sj}(2632) has been performed and a new D{sub sJ} state at a mass of 2.856 GeV/c{sup 2} has been observed. A search for Y(4260) has been performed in exclusive D{sub D} production from initial-state radi… more
Date: February 9, 2007
Creator: Palano, Antimo
Partner: UNT Libraries Government Documents Department
open access

Nucleation and growth of the Alpha-Prime Phase martensitic phase in Pu-Ga Alloys

Description: In a Pu-2.0 at% Ga alloy, it is observed experimentally that the amount of the martensitic alpha-prime product formed upon cooling the metastable delta phase below the martensite burst temperature (M{sub b}) is a function of the holding temperature and holding time of a prior conditioning (''annealing'') treatment. Before subjecting a sample to a cooling and heating cycle to form and revert the alpha-prime phase, it was first homogenized for 8 hours at 375 C to remove any microstructural memory… more
Date: February 9, 2005
Creator: Blobaum, K M; Krenn, C R; Wall, M A; Massalski, T B & Schwartz, A J
Partner: UNT Libraries Government Documents Department
open access

An imaging proton spectrometer for short-pulse laser plasma experiments

Description: Ultra intense short pulse laser pulses incident on solid targets can generate energetic protons. In additions to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better understand these laser-produced protons, we designed and constructed a novel, spatially imaging proton spectrometer that will not only provide at high-resolution the energy distribu… more
Date: February 9, 2010
Creator: Chen, H.; Hazi, A.; van Maren, R.; Chen, S.; Fuchs, J.; Gauthier, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Use of TOUGHREACT to Simulate Effects of Fluid Chemistry onInjectivity in Fractured Geothermal Reservoirs with High Ionic StrengthFluids

Description: Recent studies suggest that mineral dissolution/precipitation and clay swelling effects could have a major impact on the performance of hot dry rock (HDR) and hot fractured rock (HFR) reservoirs. A major concern is achieving and maintaining adequate injectivity, while avoiding the development of preferential short-circuiting flow paths. A Pitzer ionic interaction model has been introduced into the publicly available TOUGHREACT code for solving non-isothermal multi-phase reactive geochemical tra… more
Date: February 9, 2005
Creator: Xu, Tianfu; Zhang, Guoxiang & Pruess, Karsten
Partner: UNT Libraries Government Documents Department
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