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Hydrodynamick instabilities on ICF capsules

Description: This article summarizes our current understanding of hydrodynamic instabilities as relevant to ICF. First we discuss classical, single mode Rayleigh-Taylor instability, and nonlinear effects in the evolution of a single mode. Then we discuss multimode systems, considering: (1) the onset of nonlinearity; (2) a second order mode coupling theory for weakly nonlinear effects, and (3) the fully nonlinear regime. Two stabilization mechanisms relevant to ICF are described next: gradient scale length a… more
Date: June 7, 1991
Creator: Haan, S.W.
Partner: UNT Libraries Government Documents Department
open access

Effective theories and thresholds in particle physics

Description: The role of effective theories in probing a more fundamental underlying theory and in indicating new physics thresholds is discussed, with examples from the standard model and more speculative applications to superstring theory. 38 refs.
Date: June 7, 1991
Creator: Gaillard, M. K.
Partner: UNT Libraries Government Documents Department
open access

Enhanced geothermal systems (EGS) using CO2 as working fluid - Anovelapproach for generating renewable energy with simultaneoussequestration of carbon

Description: Responding to the need to reduce atmospheric emissions of carbon dioxide, Donald Brown (2000) proposed a novel enhanced geothermal systems (EGS) concept that would use CO{sub 2} instead of water as heat transmission fluid, and would achieve geologic sequestration of CO{sub 2} as an ancillary benefit. Following up on his suggestion, we have evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal re… more
Date: June 7, 2006
Creator: Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

Sensor Development for the Large Synoptic Survey Telescope.

Description: The Large Synoptic Survey project proposes to build an 8m-class ground-based telescope with a dedicated wide field camera. The camera consists of a large focal plane mosaic composed of multi-output CCDs with extended red response. Design considerations and preliminary characterization results for the sensors are presented in this contribution to the Workshop.
Date: June 7, 2007
Creator: O'Connor, P.; Radeka, V. & Takacs, P.
Partner: UNT Libraries Government Documents Department
open access

Interlayer Interaction and Electronic Screening in MultilayerGraphene

Description: The unusual transport properties of graphene are the direct consequence of a peculiar bandstructure near the Dirac point. We determine the shape of the {pi} bands and their characteristic splitting, and find the transition from two-dimensional to bulk character for 1 to 4 layers of graphene by angle-resolved photoemission. By detailed measurements of the {pi} bands we derive the stacking order, layer-dependent electron potential, screening length and strength of interlayer interaction by compar… more
Date: June 7, 2007
Creator: Ohta, Taisuke; Bostwick, Aaron; McChesney, J.L.; Seyller, Thomas; Horn, Karsten & Rotenberg, Eli
Partner: UNT Libraries Government Documents Department
open access

Classification of non-coding RNA using graph representations ofsecondary structure

Description: Some genes produce transcripts that function directly in regulatory, catalytic, or structural roles in the cell. These non-coding RNAs are prevalent in all living organisms, and methods that aid the understanding of their functional roles are essential. RNA secondary structure, the pattern of base-pairing, contains the critical information for determining the three dimensional structure and function of the molecule. In this work we examine whether the basic geometric and topological properties … more
Date: June 7, 2004
Creator: Karklin, Yan; Meraz, Richard F. & Holbrook, Stephen R.
Partner: UNT Libraries Government Documents Department
open access

How Can We Test Seesaw Experimentally?

Description: The seesaw mechanism for the small neutrino mass has been a popular paradigm, yet it has been believed that there is no way to test it experimentally. We present a conceivable outcome from future experiments that would convince us of the seesaw mechanism. It would involve a variety of data from LHC, ILC, cosmology, underground, and low-energy flavor violation experiments to establish the case.
Date: June 7, 2006
Creator: Buckley, Matthew R. & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department
open access

Cooperative sentry vehicles and differential GPS leapfrog

Description: As part of a project for the Defense Advanced Research Projects Agency, Sandia National Laboratories Intelligent Systems and Robotics Center is developing and testing the feasibility of using a cooperative team of robotic sentry vehicles to guard a perimeter, perform a surround task, and travel extended distances. This paper describes the authors most recent activities. In particular, this paper highlights the development of a Differential Global Positioning System (DGPS) leapfrog capability th… more
Date: June 7, 2000
Creator: Feddema, John T.; Lewis, Christopher L. & LaFarge, Robert A.
Partner: UNT Libraries Government Documents Department
open access

Silica control and materials tests at the Salton Sea geothermal field

Description: The Lawrence Livermore Laboratory maintains and operates a test facility near Niland, California, in the Imperial Valley for field studies on SSGF brine chemistry, scale and solids control, materials, and injection. Recent work in silica control and materials testing is reviewed.
Date: June 7, 1979
Creator: Quong, R.; Harrar, J. E.; McCright, R. D.; Locke, R. D.; Lorensen, L. E. & Tardiff, G. E.
Partner: UNT Libraries Government Documents Department
open access

Differencing asymptotic diffusion theory

Description: A diffusion theory is presented which extends asymptotic diffusion to non-uniform material properties. Finite difference methods for the diffusion theory naturally result in jump conditions on interfaces when appropriate.
Date: June 7, 1979
Creator: Zimmerman, G.B.
Partner: UNT Libraries Government Documents Department
open access

Inversion approach for thermal data from a convecting hydrothermal system. Revision 1

Description: Hydrothermal systems are often studied by collecting thermal gradient data and temperature-depth curves. These data contain important information about the flow field, the evolution of the hydrothermal system, and the location and nature of the ultimate heat sources. Thermal data are conventionally interpreted by the ''forward'' method; the thermal field is calculated based on selected initial conditions and boundary conditions such as temperature and permeability distributions. If the calculat… more
Date: June 7, 1985
Creator: Kasameyer, P.; Younker, L. & Hanson, J.
Partner: UNT Libraries Government Documents Department
open access

Particle physics and superstrings

Description: Implications of recent precision measurements of the standard model gauge coupling constants are discussed in the context of superstring theory. 40 refs.
Date: June 7, 1991
Creator: Gaillard, M.K. (California Univ., Berkeley, CA (United States). Dept. of Physics Lawrence Berkeley Lab., CA (United States))
Partner: UNT Libraries Government Documents Department
open access

Pulse-power circuit diagnostics for the Nova laser

Description: The Nova laser will have a large pulse power system for driving laser amplifiers, incorporating approximately 1600 flashlamp circuits. An automated system has been designed for diagnosing the condition of these flashlamp circuits. It records digitized circuit current waveforms and detects current excursions above a given threshold. In addition, it is able to fire flashlamps at a low energy to ascertain the health of the system. Data from this system can be ploted for inspection by the operator,… more
Date: June 7, 1982
Creator: Christie, D. J.; Dallum, G. E.; Gritton, D. G.; Merritt, B. T.; Whitham, K. & Berkbigler, L. W.
Partner: UNT Libraries Government Documents Department
open access

The use of the Fermilab antiproton Accumulator in medium energy physics experiments

Description: The Fermilab antiprotron Accumulator has been modified for use in a medium energy experiment. The experiment is conducted with circulating antiproton beam of momentum between 6.7 GeV/c and 3.7 GeV/c colliding with protons from an internal gas jet. Antiprotons are accumulated at the normal momentum of 8.9 GeV/c and then decelerated to the appropriate energy. It is necessary to cool the beam continually during the time it is colliding with the gas jet. The experiment requires new provisions for t… more
Date: June 7, 1988
Creator: Bharadwaj, V.; Church, M.; Harms, E.; Hsueh, S.Y.; Kells, W.; MacLachlan, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Isentropic Compression of LX-04 on the Z Accelerator

Description: Three sets of LX-04 samples of 0.18 and 0.49 mm nominal thicknesses were all dynamically loaded by Sandia's Z-accelerator with a ramp compression wave with a 200 ns rise time and about 150 kb peak stress. The LX-04/lithium fluoride samples interface velocities were measured using VISAR's. Comparisons of experimental and computational results are given. Compression and release isentropes both show some reaction and kinetic behavior of the LX-04. Experiments were also performed on fine-grained TA… more
Date: June 7, 2001
Creator: Reisman, D B; Forbes, J W; Tarver, C M; Garcia, F; Cauble, R C; Hall, C A et al.
Partner: UNT Libraries Government Documents Department
open access

Gluons and the Quark Sea at High Energies: Distributions, Polarization, Tomography

Description: This report on the science case for an Electron-Ion Collider (EIC) is the result of a ten-week program at the Institute for Nuclear Theory (INT) in Seattle (from September 13-November 19, 2010), motivated by the need to develop a strong case for the continued study of the QCD description of hadron structure in the coming decades. Hadron structure in the valence quark region will be studied extensively with the Jefferson Lab 12 GeV science program, the subject of an INT program the previous year… more
Date: June 7, 2012
Creator: Boer, Daniel; Diehl, Markus; Milner, Richard; Venugopalan, Raju; Vogelsang, Werner; Kaplan, David et al.
Partner: UNT Libraries Government Documents Department
open access

Robust Optical Richness Estimation with Reduced Scatter

Description: Reducing the scatter between cluster mass and optical richness is a key goal for cluster cosmology from photometric catalogs. We consider various modifications to the red-sequence matched filter richness estimator of Rozo et al. (2009b), and evaluate their impact on the scatter in X-ray luminosity at fixed richness. Most significantly, we find that deeper luminosity cuts can reduce the recovered scatter, finding that {sigma}{sub ln L{sub X}|{lambda}} = 0.63 {+-} 0.02 for clusters with M{sub 500… more
Date: June 7, 2012
Creator: Rykoff, E. S.; Koester, B. P.; Rozo, E.; Annis, J.; Evrard, A. E.; Hansen, S. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Baryonic B Decays

Description: No Description Available.
Date: June 7, 2013
Creator: Shiu, Jing-Ge & /Taiwan, Natl. Taiwan U.
Partner: UNT Libraries Government Documents Department
open access

The BigBoss Experiment

Description: BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra o… more
Date: June 7, 2012
Creator: Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Probing Ferroelectricity in PbZr0.2Ti0.8O3 with Polarized Soft X-rays

Description: The reduction in symmetry associated with the onset of ferroelectric order in PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT) thin films leads to a pronounced difference at the Ti L{sub 3,2} absorption edges between spectra measured with the x-ray linear polarization perpendicular and parallel to the ferroelectric polarization. We introduce a general method to analyze the observed difference spectra using atomic multiplet calculations. Moreover, we find experimental evidence for structural changes in PZ… more
Date: June 7, 2010
Creator: Arenholz, E.; van der Laan, G.; Fraile-Rodriguez, A.; Yu, P.; He, Q. & Ramesh, R.
Partner: UNT Libraries Government Documents Department
open access

Collective behavior in recent laser-plasma experiments

Description: The absorption of 1.06 ..mu.. light focused on small C/sub 8/H/sub 8/ discs has been measured in the intensity range of 10/sup 15/ - 10/sup 17/ W/cm. The data confirms the importance of collective plasma effects in determining the absorption of intense light. The measured absorption efficiencies are in the range of 30 to 40 percent, and the scattered light has a polarization dependence. The measured absorptions are shown to be inconsistent with classical inverse bremsstrahlung. Both the magnitu… more
Date: June 7, 1976
Creator: Kruer, W. L.; Haas, R. A.; Mead, W. C.; Phillion, D. W. & Rupert, V. C.
Partner: UNT Libraries Government Documents Department
open access

Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

Description: We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however f… more
Date: June 7, 2012
Creator: Kataoka, J.; Stawarz, L.; Takahashi, Y.; Cheung, C. C.; Hayashida, M.; Grandi, P. et al.
Partner: UNT Libraries Government Documents Department
open access

A Survey of Pressure Vessel Code Compliance for Super conducting RF Cryomodules

Description: Superconducting radio frequency (SRF) cavities made from niobium and cooled with liquid helium are becoming key components of many particle accelerators. The helium vessels surrounding the RF cavities, portions of the niobium cavities themselves, and also possibly the vacuum vessels containing these assemblies, generally fall under the scope of local and national pressure vessel codes. In the U.S., Department of Energy rules require national laboratories to follow national consensus pressure ve… more
Date: June 7, 2011
Creator: Peterson, Thomas; Klebaner, Arkadiy; Nicol, Tom; Theilacker, Jay; Hayano, Hitoshi; Kako, Eiji et al.
Partner: UNT Libraries Government Documents Department
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