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Radioactive gas and hydrogen removal after a LOCE at the LOFT Facility

Description: The use of a silver-zeolite halogen adsorber placed in series with a hydrogen catalytic recombiner and a cryogenic noble gas adsorber assembly constitutes a waste gas processing system (WGPS) capable of handling hydrogen and fission product gases following a Loss-of-Coolant Experiment (LOCE). This paper describes: the types and quantities of gases expected to be found at the facility after a failed-fuel LOCE; the purpose of the WGPS; and the general configuration and expected decontamination fa… more
Date: December 17, 1979
Creator: McCormick-Barger, J.W. & Sumpter, K.C.
Partner: UNT Libraries Government Documents Department
open access

ICF diagnostics. Revision 1

Description: In the past several years there have been significant advances and accomplishments in the field of Inertial Confinement Fusion (ICF) research which are directly attributable to an active experimental program supported by the development and applications of sophisticated and specialized diagnostics instruments and techniques. The continued development of high temporal-and spatial-resolution diagnostics, although with a somewhat different technical emphasis than previously, is essential for maint… more
Date: December 17, 1982
Creator: Coleman, L.W.
Partner: UNT Libraries Government Documents Department
open access

Operation of a Free-Electron Laser from the Extreme Ultraviolet to the Water Window

Description: We report results on the performance of a free-electron laser operating at a wavelength of 13.7 nm where unprecedented peak and average powers for a coherent extreme-ultraviolet radiation source have been measured. In the saturation regime, the peak energy approached 170 {micro}J for individual pulses, and the average energy per pulse reached 70 {micro}J. The pulse duration was in the region of 10 fs, and peak powers of 10 GW were achieved. At a pulse repetition frequency of 700 pulses per seco… more
Date: December 17, 2007
Creator: Ackermann, W.; Asova, G.; Ayvazyan, V.; Azima, A.; Baboi, N.; Bahr, J. et al.
Partner: UNT Libraries Government Documents Department
open access

SOFTWARE QUALITY ASSURANCE FOR EMERGENCY RESPONSE CONSEQUENCE ASSESSMENT MODELS AT DOE'S SAVANNAH RIVER SITE

Description: The Savannah River National Laboratory's (SRNL) Atmospheric Technologies Group develops, maintains, and operates computer-based software applications for use in emergency response consequence assessment at DOE's Savannah River Site. These applications range from straightforward, stand-alone Gaussian dispersion models run with simple meteorological input to complex computational software systems with supporting scripts that simulate highly dynamic atmospheric processes. A software quality assura… more
Date: December 17, 2007
Creator: Hunter, C
Partner: UNT Libraries Government Documents Department
open access

Stable SUSY breaking model with O(10) eV gravitino from combined D-term gauge mediation and U(1)' mediation

Description: We show a calculable example of stable supersymmetry (SUSY) breaking modelswith O(10) eV gravitino mass based on the combination of D-term gauge mediationand U(1)' mediation. A potential problem of the negative mass squared for theSUSY standard model (SSM) sfermions in the D-term gauge mediation is solvedby the contribution from the U(1)' mediation. On the other hand, the splittingbetween the SSM gauginos and sfermions in the U(1)' mediation iscircumvented bythe contributions from t… more
Date: December 17, 2007
Creator: Nakayama, Yu & Nakayama, Yu
Partner: UNT Libraries Government Documents Department
open access

PERTURBATION-THEORY RULES FOR COMPUTING THE SELF-ENERGY OPERATOR IN QUANTUM STATISTICAL MECHANICS

Description: Highly convenient rules are given for the general term in the time-independent perturbation-theory expansion for the self-energy operator of quantum statistical mechanics. The rules are derived by starting from the usual formalism involving time-dependent Green's functions. The well-known formulas for thermodynamic quantities in terms of the self-energy operator are included for completeness.
Date: December 17, 1962
Creator: Baym, Gordon & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

A celestial gamma-ray foreground due to the albedo of small solar system bodies and a remote probe of the interstellar cosmic ray spectrum

Description: We calculate the {gamma}-ray albedo flux from cosmic-ray (CR) interactions with the solid rock and ice in Main Belt asteroids and Kuiper Belt objects (KBOs) using the Moon as a template. We show that the {gamma}-ray albedo for the Main Belt and Kuiper Belt strongly depends on the small-body mass spectrum of each system and may be detectable by the forthcoming Gamma Ray Large Area Space Telescope (GLAST). The orbits of the Main Belt asteroids and KBOs are distributed near the ecliptic, which pas… more
Date: December 17, 2007
Creator: Moskalenko, Igor V.; Porter, Troy A.; Digel, Seth W.; Michelson, Peter F. & Ormes, Jonathan F.
Partner: UNT Libraries Government Documents Department
open access

A stable finite difference method for the elastic wave equation on complex geometries with free surfaces

Description: The isotropic elastic wave equation governs the propagation of seismic waves caused by earthquakes and other seismic events. It also governs the propagation of waves in solid material structures and devices, such as gas pipes, wave guides, railroad rails and disc brakes. In the vast majority of wave propagation problems arising in seismology and solid mechanics there are free surfaces. These free surfaces have, in general, complicated shapes and are rarely flat. Another feature, characterizing … more
Date: December 17, 2007
Creator: Appelo, D & Petersson, N A
Partner: UNT Libraries Government Documents Department
open access

The Kinematics of Molecular Cloud Cores in the Presence of Driven and Decaying Turbulence: Comparisons with Observations

Description: In this study we investigate the formation and properties of prestellar and protostellar cores using hydrodynamic, self-gravitating Adaptive Mesh Refinement simulations, comparing the cases where turbulence is continually driven and where it is allowed to decay. We model observations of these cores in the C{sup 18}O(2 {yields} 1), NH{sub 3}(1, 1), and N{sub 2}H{sup +}(1 {yields} 0) lines, and from the simulated observations we measure the linewidths of individual cores, the linewidths of the su… more
Date: December 17, 2007
Creator: Offner, S R; Krumholz, M R; Klein, R I & McKee, C F
Partner: UNT Libraries Government Documents Department
open access

Engineered and Administrative Safety Systems for the Control of Prompt Radiation Hazards at Accelerator Facilities

Description: The ANSI N43.1 Standard, currently in revision (ANSI 2007), sets forth the requirements for accelerator facilities to provide adequate protection for the workers, the public and the environment from the hazards of ionizing radiation produced during and from accelerator operations. The Standard also recommends good practices that, when followed, provide a level of radiation protection consistent with those established for the accelerator communities. The N43.1 Standard is suitable for all accele… more
Date: December 17, 2007
Creator: Liu, James C.; Vylet, Vashek & Walker, Lawrence S.
Partner: UNT Libraries Government Documents Department
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Proceedings: special panel on geothermal model intercomparison study

Description: Separate abstracts were prepared for five papers. Two papers were abstracted previously for EDB. Five panel responses to the project, three workshop session summaries, and conclusions drawn are also included in this report. (MHR)
Date: December 17, 1980
Partner: UNT Libraries Government Documents Department
open access

High threshold HR (highly reflective) coatings at 1064 nm

Description: We have conducted as extensive series of laser damage measurements on highly reflective (HR) dielectric coatings which have yielded 1064-nm thresholds as high as 40 J/cm{sup 2} for 8- to 10-ns pulses at pulse-repetition frequencies (PRF) of 10 Hz. Moreover, by laser conditioning these coatings with subthreshold pulses, the thresholds of some coatings were raised to levels exceeding 70 J/cm{sup 2}. These are the highest threshold dielectric HR coatings that we have tested in this regime. The coa… more
Date: December 17, 1990
Creator: Rainer, F.; DeMarco, F. P.; Hunt, J. T.; Morgan, A. J.; Mott, L. P.; Marcelja, F. et al.
Partner: UNT Libraries Government Documents Department
open access

Sodium/water pool-deposit bed model of the CONACS code. [LMFBR]

Description: A new Pool-Bed model of the CONACS (Containment Analysis Code System) code represents a major advance over the pool models of other containment analysis code (NABE code of France, CEDAN code of Japan and CACECO and CONTAIN codes of the United States). This new model advances pool-bed modeling because of the number of significant materials and processes which are included with appropriate rigor. This CONACS pool-bed model maintains material balances for eight chemical species (C, H/sub 2/O, Na, … more
Date: December 17, 1983
Creator: Peak, R.D.
Partner: UNT Libraries Government Documents Department
open access

Laser conditioning and electronic defect measurements of HfO sub 2 and SiO sub 2 thin films

Description: Multilayer HfO{sub 2}/SiO{sub 2} high reflectors (HR) and polarizers show a permanent increase in their 1064-nm damage thresholds following laser conditioning at subthreshold fluences. Threshold increases of 2--3x are typical. In an effort to better understand the conditioning effect we have made laser conditioning and electronic property measurements on single layers of these two materials. The laser damage threshold of 1-{mu}m thick e-beam deposited SiO{sub 2} was increased by laser condition… more
Date: December 17, 1990
Creator: Kozlowski, M.R.; Staggs, M.; Rainer, F. (Lawrence Livermore National Lab., CA (USA)) & Stathis, J.H. (International Business Machines Corp., Yorktown Heights, NY (USA). Thomas J. Watson Research Center)
Partner: UNT Libraries Government Documents Department
open access

Optical characterization of damage resistant kilolayer'' rugate filters

Description: Multilayer dielectric optical coatings produced by high temperature plasma-assisted chemical vapor deposition (PCVD) have been previously shown to have very high surface and bulk damage thresholds (above 40J/cm{sup 2}). Because these experimental coatings are deposited on tubular substrates, conventional wavelength scanning cannot accurately measure the coating peak reflectance and bandwidth. Measurement of the variation of transmittance with incidence angle at fixed wavelength permits analysis… more
Date: December 17, 1990
Creator: Elder, M.L.; Jancaitis, K.S.; Milam, D. & Campbell, J.H.
Partner: UNT Libraries Government Documents Department
open access

Damage resistant optics for a mega-joule solid-state laser

Description: Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence, LLNL is developing plans to upgrade the current 120 kJ solid state (Nd{sup +3}-phosphate glass) Nova laser to a 1.5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajo… more
Date: December 17, 1990
Creator: Campbell, J.H.; Rainer, F.; Kozlowski, M.; Wolfe, C.R.; Thomas, I. & Milanovich, F.
Partner: UNT Libraries Government Documents Department
open access

Combining nonlinear multiresolution system and vector quantization for still image compression

Description: It is popular to use multiresolution systems for image coding and compression. However, general-purpose techniques such as filter banks and wavelets are linear. While these systems are rigorous, nonlinear features in the signals cannot be utilized in a single entity for compression. Linear filters are known to blur the edges. Thus, the low-resolution images are typically blurred, carrying little information. We propose and demonstrate that edge-preserving filters such as median filters can be u… more
Date: December 17, 1993
Creator: Wong, Y.
Partner: UNT Libraries Government Documents Department
open access

Correlated Nitrogen and Carbon Anomalies in an Anhydrous Interplanetary Dust Particle - Implications for Extraterrestrial Organic Matter Accreted by the Prebiotic Earth

Description: Given the ubiquitous presence of H and N isotopic anomalies in interplanetary dust particles (IDPs) and their probable association with carbonaceous material, the lack of similar isotopic anomalies in C has been a major conundrum. We report here the first observation of correlated N and C isotopic anomalies in organic matter within an anhydrous IDP. The {sup 15}N composition of the anomalous region is the highest seen to date in an IDP and is accompanied by a moderate depletion in {sup 13}C. Ou… more
Date: December 17, 2003
Creator: Floss, C; Stadermann, F J; Bradley, J P; Dai, Z; Bajt, S & Graham, G
Partner: UNT Libraries Government Documents Department
open access

Kinematics of Gamma-Ray Burst and their Relationship to Afterglows

Description: A strong correlation is reported between gamma-ray burst (GRB) pulse lags and afterglow jet-break times for the set of bursts (seven) with known redshifts, luminosities, pulse lags, and jet-break times. This may be a valuable clue toward understanding the connection between the burst and afterglow phases of these events. The relation is roughly linear (i.e. doubling the pulse lag in turn doubles the jet break time) and thus implies a simple relationship between these quantities. We suggest that… more
Date: December 17, 2001
Creator: Salmonson, J D
Partner: UNT Libraries Government Documents Department
open access

Using a two-step matrix solution to reduce the run time in KULL's magnetic diffusion package

Description: Recently a Resistive Magnetohydrodynamics (MHD) package has been added to the KULL code. In order to be compatible with the underlying hydrodynamics algorithm, a new sub-zonal magnetics discretization was developed that supports arbitrary polygonal and polyhedral zones. This flexibility comes at the cost of many more unknowns per zone - approximately ten times more for a hexahedral mesh. We can eliminate some (or all, depending on the dimensionality) of the extra unknowns from the global matrix… more
Date: December 17, 2010
Creator: Brunner, T A & Kolev, T V
Partner: UNT Libraries Government Documents Department
open access

The use of a high-order MEMS deformable mirror in the Gemini Planet Imager

Description: We briefly review the development history of the Gemini Planet Imager's 4K Boston Micromachines MEMS deformable mirror. We discuss essential calibration steps and algorithms to control the MEMS with nanometer precision, including voltage-phase calibration and influence function characterization. We discuss the integration of the MEMS into GPI's Adaptive Optics system at Lawrence Livermore and present experimental results of 1.5 kHz closed-loop control. We detail mitigation strategies in the cor… more
Date: December 17, 2010
Creator: Poyneer, L. A.; Bauman, B.; Cornelissen, S.; Jones, S.; Macintosh, B.; Palmer, D. et al.
Partner: UNT Libraries Government Documents Department
open access

S-Band Sheet Beam Klystron Research and Development at SLAC

Description: No Description Available.
Date: December 17, 2012
Creator: Jensen, Aaron; Fazio, Michael V.; Haase, Andrew; Jongewaard, Erik N.; Martin, David W.; Neilson, Jeffrey et al.
Partner: UNT Libraries Government Documents Department
open access

CORROSION ISSUES ASSOCIATED WITH AUSTENITIC STAINLESS STEEL COMPONENTS USED IN NUCLEAR MATERIALS EXTRACTION AND SEPARATION PROCESSES

Description: This paper illustrated the magnitude of the systems, structures and components used at the Savannah River Site for nuclear materials extraction and separation processes. Corrosion issues, including stress corrosion cracking, pitting, crevice corrosion and other corrosion induced degradation processes are discussed and corrosion mitigation strategies such as a chloride exclusion program and corrosion release testing are also discussed.
Date: December 17, 2012
Creator: Mickalonis, J.; Louthan, M. & Sindelar, R.
Partner: UNT Libraries Government Documents Department
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