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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

Statistical characterization of dislocation ensembles

Description: We outline a method to study the spatial and orientation statistics of dynamical dislocation systems by modeling the dislocations as a stochastic fiber process. Statistical measures have been introduced for the density, velocity, and flux of dislocations, and the connection between these measures and the dislocation state and plastic distortion rate in the crystal is explained. A dislocation dynamics simulation model has been used to extract numerical data to study the evolution of these statis… more
Date: May 17, 2006
Creator: El-Azab, A.; Deng, J. & Tang, M.
Partner: UNT Libraries Government Documents Department
open access

Digitral Down Conversion Technology for Tevatron Beam Line Tuner at FNAL

Description: Fermilab is presently in Run II collider operations and is developing instrumentation to improve luminosity. Improving the orbit matching between accelerator components using a Beam Line Tuner (BLT) can improve the luminosity. Digital Down Conversion (DDC) has been proposed as a method for making more accurate beam position measurements. Fermilab has implemented a BLT system using a DDC technique to measure orbit oscillations during injections from the Main Injector to the Tevatron. The output … more
Date: March 17, 2008
Creator: Schappert, W.; Lorman, E.; Scarpine, V.; Ross, M.C.; Sebek, J.; Straumann, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Water, law, science

Description: In a world with water resources severely impacted bytechnology, science must actively contribute to water law. To this end,this paper is an earth scientist s attempt to comprehend essentialelements of water law, and to examine their connections to science.Science and law share a common logical framework of starting with apriori prescribed tenets, and drawing consistent inferences. In science,observationally established physical laws constitute the tenets, while inlaw, they stem from social valu… more
Date: October 17, 2007
Creator: Narasimhan, T.N.
Partner: UNT Libraries Government Documents Department
open access

CAMS/LLNL Ion Source Efficiency Revisited

Description: No Description Available.
Date: April 17, 2007
Creator: Fallon, S. J.; Guilderson, T. P. & Brown, T. A.
Partner: UNT Libraries Government Documents Department
open access

ENHANCED CHEMICAL CLEANING: A NEW PROCESS FOR CHEMICALLY CLEANING SAVANNAH RIVER WASTE TANKS

Description: The Savannah River Site (SRS) has 49 high level waste (HLW) tanks that must be emptied, cleaned, and closed as required by the Federal Facilities Agreement. The current method of chemical cleaning uses several hundred thousand gallons per tank of 8 weight percent (wt%) oxalic acid to partially dissolve and suspend residual waste and corrosion products such that the waste can be pumped out of the tank. This adds a significant quantity of sodium oxalate to the tanks and, if multiple tanks are cle… more
Date: January 17, 2008
Creator: Ketusky, E; Neil Davis, N & Renee Spires, R
Partner: UNT Libraries Government Documents Department
open access

Numerical studies of fluid-rock interactions in EnhancedGeothermal Systems (EGS) with CO2 as working fluid

Description: There is growing interest in the novel concept of operating Enhanced Geothermal Systems (EGS) with CO{sub 2} instead of water as heat transmission fluid. Initial studies have suggested that CO{sub 2} will achieve larger rates of heat extraction, and can offer geologic storage of carbon as an ancillary benefit. Fluid-rock interactions in EGS operated with CO{sub 2} are expected to be vastly different in zones with an aqueous phase present, as compared to the central reservoir zone with anhydrous… more
Date: January 17, 2008
Creator: Xu, Tianfu; Pruess, Karsten & Apps, John
Partner: UNT Libraries Government Documents Department
open access

137Cs Inter-Plant Concentration Ratios Provide a Predictive Tool for Coral Atolls with Distinct Benefits Over Transfer Factors

Description: Inter-plant concentration ratios (IPCR), [Bq g{sup -1} {sup 137}Cs in coral atoll tree food-crops/Bq g{sup -1} {sup 137}Cs in leaves of native plant species whose roots share a common soil volume], can replace transfer factors (TF) to predict {sup 137}Cs concentration in tree food-crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes a… more
Date: July 17, 2007
Creator: Robison, W L; Hamilton, T F; Bogen, K; Corado, C L & Kehl, S R
Partner: UNT Libraries Government Documents Department
open access

Proceedings of RIKEN BNL Research Center Workshop, Volume 91, RBRC Scientific Review Committee Meeting

Description: The ninth evaluation of the RIKEN BNL Research Center (RBRC) took place on Nov. 17-18, 2008, at Brookhaven National Laboratory. The members of the Scientific Review Committee (SRC) were Dr. Dr. Wit Busza (Chair), Dr. Miklos Gyulassy, Dr. Akira Masaike, Dr. Richard Milner, Dr. Alfred Mueller, and Dr. Akira Ukawa. We are pleased that Dr. Yasushige Yano, the Director of the Nishina Institute of RIKEN, Japan participated in this meeting both in informing the committee of the activities of the Nishi… more
Date: November 17, 2008
Creator: Samios, N. P.
Partner: UNT Libraries Government Documents Department
open access

Active Damping of the E-P Instability at the Los Alamos Proton Storage Ring

Description: A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). The feedback system configuration, setup procedures, and optimization of performance are described. Results of several experimental tests… more
Date: March 17, 2008
Creator: Macek, R. J.; Assadi, S.; Byrd, J. M.; Deibele, C. E.; Henderson, S. D.; Lee, S. Y. et al.
Partner: UNT Libraries Government Documents Department
open access

In-situ probing of lattice response in shock compressed materials using x-ray diffraction

Description: Lattice level measurements of material response under extreme conditions are required to build a phenomenological understanding of the shock response of solids. We have successfully used laser produced plasma x-ray sources coincident with laser driven shock waves to make in-situ measurements of the lattice response during shock compression for both single crystal and polycrystalline materials. Using a detailed analysis of shocked single crystal iron which has undergone the {alpha} - {var_epsilo… more
Date: July 17, 2007
Creator: Hawreliak, J.; Butterfield, M.; Davies, H.; El-Dasher, B.; Higginbotham, A.; Kalantar, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Downregulation of Protein 4.1R impairs centrosome function,bipolar spindle organization and anaphase

Description: Centrosomes nucleate and organize interphase MTs and areinstrumental in the assembly of the mitotic bipolar spindle. Here wereport that two members of the multifunctional protein 4.1 family havedistinct distributions at centrosomes. Protein 4.1R localizes to maturecentrioles whereas 4.1G is a component of the pericentriolar matrixsurrounding centrioles. To selectively probe 4.1R function, we used RNAinterference-mediated depletion of 4.1R without decreasing 4.1Gexpression. 4.1R downregulation r… more
Date: March 17, 2006
Creator: Spence, Jeffrey R.; Go, Minjoung M.; Bahmanyar, S.; Barth,A.I.M. & Krauss, Sharon Wald
Partner: UNT Libraries Government Documents Department
open access

A CCD Camera with Electron Decelerator for Intermediate Voltage Electron Microscopy

Description: Electron microscopists are increasingly turning to Intermediate Voltage Electron Microscopes (IVEMs) operating at 300 - 400 kV for a wide range of studies. They are also increasingly taking advantage of slow-scan charge coupled device (CCD) cameras, which have become widely used on electron microscopes. Under some conditions CCDs provide an improvement in data quality over photographic film, as well as the many advantages of direct digital readout. However, CCD performance is seriously degraded… more
Date: March 17, 2008
Creator: Downing, Kenneth H; Downing, Kenneth H. & Mooney, Paul E.
Partner: UNT Libraries Government Documents Department
open access

Microbunching and Beam Break Up in DUV FEL Accelerator

Description: We present the results of electron beam longitudinal modulation studies in the DUV-FEL accelerator. For bunch length determination we used the 'zero-phasing' method, based on a measurement of the chirped electron bunch energy spectra. The measurements revealed a spiky structure in the longitudinal phase space [1]. A model based on space charge effect is considered [2] to explain of the obtained phenomena. The analysis of the energy spectra has shown a sensitivity of the structure to the electro… more
Date: March 17, 2008
Creator: Shaftan, T.; Carr, L.; Loos, H.; Sheehy, B.; Graves, William S.; Huang, Z. et al.
Partner: UNT Libraries Government Documents Department
open access

Process Control Minitoring by Stress Response

Description: Environmental contamination with a variety of pollutants hasprompted the development of effective bioremediation strategies. But howcan these processes be best monitored and controlled? One avenue underinvestigation is the development of stress response systems as tools foreffective and general process control. Although the microbial stressresponse has been the subject of intensive laboratory investigation, theenvironmental reflection of the laboratory response to specific stresseshas been litt… more
Date: April 17, 2006
Creator: Hazen, Terry C. & Stahl, David A.
Partner: UNT Libraries Government Documents Department
open access

Estimating large-scale fracture permeability of unsaturatedrockusing barometric pressure data

Description: We present a three-dimensional modeling study of gas flow inthe unsaturated fractured rock of Yucca Mountain. Our objective is toestimate large-scale fracture permeability, using the changes insubsurface pneumatic pressure in response to barometric pressure changesat the land surface. We incorporate the field-measured pneumatic datainto a multiphase flow model for describing the coupled processes ofliquid and gas flow under ambient geothermal conditions. Comparison offield-measured pneumatic da… more
Date: May 17, 2005
Creator: Wu, Yu-Shu; Zhang, Keni & Liu, Hui-Hai
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

Counting constituents in molecular complexes by fluorescence photon antibunching

Description: Modern single molecule fluorescence microscopy offers new, highly quantitative ways of studying the systems biology of cells while keeping the cells healthy and alive in their natural environment. In this context, a quantum optical technique, photon antibunching, has found a small niche in the continuously growing applications of single molecule techniques to small molecular complexes. Here, we review some of the most recent applications of photon antibunching in biophotonics, and we provide a … more
Date: April 17, 2007
Creator: Fore, S; Laurence, T; Hollars, C & Huser, T
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

A Lattice with Larger Momentum Compaction for the NLC Main Damping Rings

Description: Previous lattice designs for the Next Linear Collider Main Damping Rings [1] have met the specifications for equilibrium emittance, damping rate and dynamic aperture. Concerns about the effects of the damping wiggler on the beam dynamics [2] led to the aim of reducing the total length of the wiggler to a minimum consistent with the required damping rate, so high-field dipoles were used to provide a significant energy loss in the arcs. However, recent work has shown that the wiggler effects may … more
Date: March 17, 2008
Creator: Woodley, M.; Raubenheimer, Tor O.; Wu, J.; Wolski, A. & /SLAC /LBL, Berkeley
Partner: UNT Libraries Government Documents Department
open access

Thermal Neutron Capture Cross Sections of the PalladiumIsotopes

Description: Precise gamma-ray thermal neutron capture cross sectionshave been measured at the Budapest Reactor for all elements withZ=1-83,92 except for He and Pm. These measurements and additional datafrom the literature been compiled to generate the Evaluated Gamma-rayActivation File (EGAF), which is disseminated by LBNL and the IAEA. Thesedata are nearly complete for most isotopes with Z<20 so the totalradiative thermal neutron capture cross sections can be determineddirectly from the decay scheme. For … more
Date: July 17, 2006
Creator: Firestone, R.B.; Krticka, M.; McNabb, D.P.; Sleaford, B.; Agvaanluvsan, U.; Belgya, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Fragmentation Cross Sections of 290 and 400 MeV/nucleon 12C Beamson Elemental Targets

Description: Charge-changing and fragment production cross sections at 0circ have been obtained for interactions of 290 MeV/nucleon and 400MeV/nucleon carbon beams with C, CH2, Al, Cu, Sn, and Pb targets. Thesebeams are relevant to cancer therapy, space radiation, and the productionof radioactive beams. We compare to previously published results using Cand CH2 targets at similar beam energies. Due to ambiguities arising fromthe presence of multiple fragments on many events, previous publicationshave reporte… more
Date: March 17, 2007
Creator: Zeitlin, C.; Guetersloh, S.; Heilbronn, L.; Miller, J.; Fukumura,A.; Iwata, Y. et al.
Partner: UNT Libraries Government Documents Department
open access

Efficient computation of matched solutions of the KV envelope equations for periodic focusing lattices.

Description: A new iterative method is developed to numerically calculate the periodic, matched beam envelope solution of the coupled Kapchinskij-Vladimirskij (KV) equations describing the transverse evolution of a beam in a periodic, linear focusing lattice of arbitrary complexity. Implementation of the method is straightforward. It is highly convergent and can be applied to all usual parameterizations of the matched envelope solutions. The method is applicable to all classes of linear focusing lattices wi… more
Date: January 17, 2006
Creator: Lund, S M; Chilton, S H & Lee, E P
Partner: UNT Libraries Government Documents Department
open access

Modeling geologic storage of carbon dioxide: Comparison of non-hysteretic and hysteretic characteristic curves

Description: Numerical models of geologic storage of carbon dioxide (CO2)in brine-bearing formations use characteristic curves to represent theinteractions of non-wetting-phase CO2 and wetting-phase brine. When aproblem includes both injection of CO2 (a drainage process) and itssubsequent post-injection evolution (a combination of drainage andwetting), hysteretic characteristic curves are required to correctlycapture the behavior of the CO2 plume. In the hysteretic formulation,capillary pressure and relativ… more
Date: July 17, 2006
Creator: Doughty, Christine
Partner: UNT Libraries Government Documents Department
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