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The U5. 0 Undulator for the ALS

Description: the U5.0 Undulator, and 89 period, 5 cm period length, 4.6 m long insertion device has been designed, is being fabricated and is scheduled for completion in early 1992. This undulator will be the first high brightness source, in the 50 to 1500 eV range, for the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory. A hybrid magnetic configuration using Nd-Fe-B permanent magnet material and vanadium permendur poles has been selected to achieve the field quality needed to meet performan… more
Date: July 15, 1991
Creator: Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.V.; Humphries, D.; Kincaid, B. et al.
Partner: UNT Libraries Government Documents Department
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Space propulsion by fusion in a magnetic dipole

Description: The unique advantages of fusion rocket propulsion systems for distant missions are explored using the magnetic dipole configurations as an example. The dipole is found to have features well suited to space applications. Parameters are presented for a system producing a specific power of kW/kg, capable of interplanetary flights to Mars in 90 days and to Jupiter in a year, and of extra-solar-system flights to 1000 astronomical units (the Tau mission) in 20 years. This is about 10 times better spe… more
Date: July 15, 1991
Creator: Teller, E.; Glass, A.J.; Fowler, T.K. (Lawrence Livermore National Lab., CA (United States)); Hasegawa, A. (AT and T Bell Labs., Murray Hill, NJ (United States)) & Santarius, J.F. (Wisconsin Univ., Madison, WI (United States). Fusion Technology Inst.)
Partner: UNT Libraries Government Documents Department
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Improved Approach to Characterizing and Presenting Streak Camera Performance

Description: The performance of a streak camera recording system is strongly linked to the technique used to amplify, detect and quantify the streaked image. At the Lawrence Livermore National Laboratory (LLNL) streak camera images have been recorded both on film and by fiber-optically coupling to charge-coupled devices (CCD's). During the development of a new process for recording these images (lens coupling the image onto a cooled CCD) the definitions of important performance characteristics such as resol… more
Date: July 15, 1985
Creator: Wiedwald, J. D. & Jones, B. A.
Partner: UNT Libraries Government Documents Department
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An Implicit "Drift-Lorentz" Particle Mover for Plasma and Beam Simulations

Description: In order to efficiently perform particle simulations in systems with widely varying magnetization, we developed a drift-Lorentz mover, which interpolates between full particle dynamics and drift kinetics in such a way as to preserve a physically correct gyroradius and particle drifts for both large and small ratios of the timestep to the cyclotron period. In order to extend applicability of the mover to systems with plasma frequency exceeding the cyclotron frequency such as one may have with fu… more
Date: July 15, 2008
Creator: Friedman, A.; Grote, D. P.; Vay, J. L. & Cohen, R. H.
Partner: UNT Libraries Government Documents Department
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Gravity monitoring of CO2 movement during sequestration: Model studies

Description: We examine the relative merits of gravity measurements as a monitoring tool for geological CO{sub 2} sequestration in three different modeling scenarios. The first is a combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the second is sequestration in a brine formation, and the third is for a coalbed methane formation. EOR/sequestration petroleum reservoirs have relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine… more
Date: July 15, 2008
Creator: Gasperikova, E. & Hoversten, G.M.
Partner: UNT Libraries Government Documents Department
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UXO detection and identification based on intrinsic target polarizabilities: A case history

Description: Electromagnetic induction data parameterized in time dependent object intrinsic polarizabilities allow discrimination of unexploded ordnance (UXO) from false targets (scrap metal). Data from a cart-mounted system designed for discrimination of UXO with 20 mm to 155 mm diameters are used. Discrimination of UXO from irregular scrap metal is based on the principal dipole polarizabilities of a target. A near-intact UXO displays a single major polarizability coincident with the long axis of the obje… more
Date: July 15, 2008
Creator: Gasperikova, E.; Smith, J.T.; Morrison, H.F.; Becker, A. & Kappler, K.
Partner: UNT Libraries Government Documents Department
open access

Characterization of Surplus Plutonium for Disposition Options

Description: The United States (U.S.) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Except for materials that remain in use for programs outside of national defense, including programs for nuclear-energy development, the surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. Some ite… more
Date: July 15, 2008
Creator: Allender, Jeffrey S.; Moore, Edwin N. & Davies, Scott H.
Partner: UNT Libraries Government Documents Department
open access

A Semi-Analytical Solution for Large-Scale Injection-Induced PressurePerturbation and Leakage in a Laterally Bounded Aquifer-AquitardSystem

Description: A number of (semi-)analytical solutions are available to drawdown analysis and leakage estimation of shallow aquifer-aquitard systems. These solutions assume that the systems are laterally infinite. When a large-scale pumping from (or injection into) an aquifer-aquitard system of lower specific storativity occurs, induced pressure perturbation (or hydraulic head drawdown/rise) may reach the lateral boundary of the aquifer. We developed semi-analytical solutions to address the induced pressure p… more
Date: July 15, 2008
Creator: Zhou, Quanlin; Birkholzer, Jens T. & Tsang, Chin-Fu
Partner: UNT Libraries Government Documents Department
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Protein-Nanocrystal Conjugates Support a Single Filament Polymerization Model in R1 Plasmid Segregation

Description: To ensure inheritance by daughter cells, many low-copy number bacterial plasmids, including the R1 drug-resistance plasmid, encode their own DNA segregation systems. The par operon of plasmid R1 directs construction of a simple spindle structure that converts free energy of polymerization of an actin-like protein, ParM, into work required to move sister plasmids to opposite poles of rod-shaped cells. The structures of individual components have been solved, but little is known about the ultrast… more
Date: July 15, 2008
Creator: Choi, Charina L.; Claridge, Shelley A.; Garner, Ethan C.; Alivisatos, A. Paul & Mullins, R. Dyche
Partner: UNT Libraries Government Documents Department
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Using 3-D Modeling to Improve the Efficiency for Removing Plutonium Processing Equiment From Gloveboxes at the Plutonium Finishang Plant

Description: The Plutonium Finishing Plant at the Department of Energy's Hanford Site in southeastern Washington State began operations in 1949 to process plutonium and plutonium products. Its primary mission was to produce plutonium metal, fabricate weapons parts, and stabilize reactive materials. These operations, and subsequent activities, were performed in production lines, consisting primarily of hundreds of gloveboxes. Over the years, these gloveboxes and attendant processes have been continuously mod… more
Date: July 15, 2008
Creator: Crow, S. H.; Kyle, R. N. & Minette, M. J.
Partner: UNT Libraries Government Documents Department
open access

Deletion of ultraconserved elements yields viable mice

Description: Ultraconserved elements have been suggested to retainextended perfect sequence identity between the human, mouse, and ratgenomes due to essential functional properties. To investigate thenecessities of these elements in vivo, we removed four non-codingultraconserved elements (ranging in length from 222 to 731 base pairs)from the mouse genome. To maximize the likelihood of observing aphenotype, we chose to delete elements that function as enhancers in amouse transgenic assay and that are near ge… more
Date: July 15, 2007
Creator: Ahituv, Nadav; Zhu, Yiwen; Visel, Axel; Holt, Amy; Afzal, Veena; Pennacchio, Len A. et al.
Partner: UNT Libraries Government Documents Department
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A study of vacuum arc ion velocities using a linear set of probes

Description: The most likely velocity of ions moving away from vacuum arc cathode spots was measured using a set of probes along the path of plasma expansion. The goal was to determine how much, if any, change of the ion drift velocity occurs in the expanded plasma. The arc discharge current was perturbed to create plasma density markers whose travel is picked up by the set of probes. It was found that the perturbation with current oscillations did not result in consistent data because ion current maxima an… more
Date: July 15, 2008
Creator: Hohenbild, Stefan; Grubel, Christoph; Yushkov, Georgy Yu.; Oks, Efim M. & Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

Inertial effects in laser-driven ablation

Description: The gasdynamic partial differential equations (PDE's) governing the motion of an ablatively accelerated target (rocket) contain an inertial force term that arises from acceleration of the reference frame in which the PDE's are written. We give a simple, intuitive description of this effect, and estimate its magnitude and parametric dependences by means of approximate analytical formulas inferred from our computer hydrocode calculations. Often this inertial term is negligible, but for problems i… more
Date: July 15, 1983
Creator: Harrach, R.J.; Szeoke, A. & Howard, W.M.
Partner: UNT Libraries Government Documents Department
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Use of the LLNL 40 kV electric gun to study the shock response of 21-6-9 stainless steel

Description: Exploding foil-flyer plate (''electric gun'') methods have been used to shock 21-6-9 stainless steel over a wide range of shock pulse amplitudes (20 to 53 GPa) and durations (10 to 70 ns). Dislocation generation and twinning have been studied in recovered specimens with the results providing support for the concept of finite rate plastic processes. 24 refs., 6 figs., 1 tab.
Date: July 15, 1987
Creator: Brusso, J. A.; Mikkola, D. E.; Bloom, G.; Lee, R. S. & Von Holle, W.
Partner: UNT Libraries Government Documents Department
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Varied line-space gratings and applications

Description: This paper presents a straightforward analytical and numerical method for the design of a specific type of varied line-space grating system. The mathematical development will assume plane or nearly-plane spherical gratings which are illuminated by convergent light, which covers many interesting cases for synchrotron radiation. The gratings discussed will have straight grooves whose spacing varies across the principal plane of the grating. Focal relationships and formulae for the optical grating… more
Date: July 15, 1991
Creator: McKinney, W.R.
Partner: UNT Libraries Government Documents Department
open access

Charged-particle beam: a safety mandate

Description: The Advanced Test Accelerator (ATA) is a recent development in the field of charged particle beam research at Lawrence Livermore National Laboratory. With this experimental apparatus, researchers will characterize intense pulses of electron beams propagated through air. Inherent with the ATA concept was the potential for exposure to hazards, such as high radiation levels and hostile breathing atmospheres. The need for a comprehensive safety program was mandated; a formal system safety program w… more
Date: July 15, 1983
Creator: Young, K.C.
Partner: UNT Libraries Government Documents Department
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Even-parity quartet autodetaching states of He/sup -/

Description: The total photodetachment cross section of the metastable, (1s2s2p) /sup 4/P/sup 0/ state of He/sup -/ has been recently measured at several wavelengths between 10 ..mu.. and 308 nm. As part of these calculations, the even parity, quartet, autodetaching states of He/sup -/ which are optically connected to the metastable /sup 4/P/sup 0/ state and which are associated with the n = 2 and n = 3 states of He were studied. In both the photodetachment and electron scattering calculations, extensive co… more
Date: July 15, 1981
Creator: Hazi, A.U.
Partner: UNT Libraries Government Documents Department
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Dipole strength functions in the actinide mass region

Description: We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.
Date: July 15, 1987
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Partner: UNT Libraries Government Documents Department
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ASSESS (Analytic System and Software for Evaluating Safeguards and Security) update: Current status and future developments

Description: The Analytic System and Software for Evaluating Safeguards and Security (ASSESS) has been released for use by DOE field offices and their contractors. In October, 1989, we offered a prototype workshop to selected representatives of the DOE community. Based on the prototype results, we held the first training workshop at the Central Training Academy in January, 1990. Four additional workshops are scheduled for FY 1990. ASSESS is a state-of-the-art analytical tool for management to conduct integr… more
Date: July 15, 1990
Creator: Al-Ayat, R.A. (Lawrence Livermore National Lab., CA (USA)); Cousins, T.D. (USDOE, Washington, DC (USA)) & Hoover, E.R. (Sandia National Labs., Albuquerque, NM (USA))
Partner: UNT Libraries Government Documents Department
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Activated barrier for protection of special nuclear materials in vital areas

Description: The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide t… more
Date: July 15, 1984
Creator: Timm, R. E.; Miranda, J. E.; Reigle, D. L. & Valente, A. D.
Partner: UNT Libraries Government Documents Department
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Fast pulsars, strange stars: An opportunity in radio astronomy

Description: The world's data on radio pulsars is not expected to represent the underlying pulsar population because of a search bias against detection of short periods, especially below 1 ms. Yet pulsars in increasing numbers with periods right down to this limit have been discovered suggesting that there may be even shorter ones. If pulsars with periods below 1/2 ms were found, the conclusion that the confined hadronic phase of nucleons and nuclei is only metastable would be almost inescapable. The plausi… more
Date: July 15, 1990
Creator: Glendenning, N.K.
Partner: UNT Libraries Government Documents Department
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An intensity interferometer for soft x-rays

Description: We designed and built an intensity interferometer to characterize the spatial coherence of a soft x-ray undulator beam. The beam source size and shape can be determined from the measured coherence function. The instrument is 400 mm long and is mounted on a standard 204-mm diameter flange. This compact design is readily adaptable to other beamlines with sources of sufficient spectral brightness. Details of the interferometer design and performance are presented. We anticipate that when this tech… more
Date: July 15, 1994
Creator: Yang, L.; McNulty, I. & Gluskin, E.
Partner: UNT Libraries Government Documents Department
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Performance of a high resolution, high flux density SGM undulator beamline at the ALS

Description: The performance of ALS beamline 7.0 is described. This is an integrated system for delivering radiation from a 5cm period undulator to spectroscopy and microscopy experiments across the range of photon energies from 60eV to 1200eV. The beamline is engineered to deliver the highest possible flux, with negligible deformation of the optic surfaces due to heating. Two experiment stations are served with rapid interchangeability. We report on the measured operational parameters, the resolution and f… more
Date: July 15, 1994
Creator: Warwick, T.; Heimann, P.; Mossessian, D.; McKinney, W. & Padmore, H.
Partner: UNT Libraries Government Documents Department
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