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A 10-Hz Terawatt Class Ti:Sapphire Laser System: Development and Applications (open access)

A 10-Hz Terawatt Class Ti:Sapphire Laser System: Development and Applications

We developed a two stage Ti:Sapphire laser system to generate 16 mJ/80fs laser pulses at the pulse repetition rate of 10 Hz. The key deriver for the present design is implementing a highly efficient symmetric confocal pre-amplifier and employing a simple, inexpensive synchronization scheme relying only on a commercial digital delay-generator. We characterized the amplified pulses in spatial-, spectral-, and temporal-domains. The laser system was used to investigate various nonlinear optical processes, and to modify the optical properties of metal- and semiconductor-surfaces. We are currently building a third amplifier to boost the laser power to the multi-terawatt range.
Date: January 12, 2010
Creator: Sharma, A. K.; Smedley, J.; Tsang, T. & Rao, T.
System: The UNT Digital Library
3D Simulations of the NIF Indirect Drive Ignition Target Design (open access)

3D Simulations of the NIF Indirect Drive Ignition Target Design

The radiation hydrodynamics code Hydra is used to quantify the sensitivity of different NIF ignition point designs to several 3D effects. Each of the 48 NIF quads is included in the calculations and is allowed to have different power. With this model they studied the effect on imploded core symmetry of discrete laser spots (as opposed to idealized azimuthally-averaged rings) and random variations in laser power.
Date: January 5, 2010
Creator: Jones, O. S.; Milovich, J. L.; Callahan, D. A.; Edwards, M. J.; Landen, O. L.; Salmonson, J. D. et al.
System: The UNT Digital Library
Abbreviated Pandemic Influenza Planning Template for Primary Care Offices (open access)

Abbreviated Pandemic Influenza Planning Template for Primary Care Offices

The Abbreviated Pandemic Influenza Plan Template for Primary Care Provider Offices is intended to assist primary care providers and office managers with preparing their offices for quickly putting a plan in place to handle an increase in patient calls and visits, whether during the 2009-2010 influenza season or future influenza seasons.
Date: January 1, 2010
Creator: CHE, HCTT
System: The UNT Digital Library
Apical polarity in three-dimensional culture systems: where to now? (open access)

Apical polarity in three-dimensional culture systems: where to now?

Delineation of the mechanisms that establish and maintain the polarity of epithelial tissues is essential to understanding morphogenesis, tissue specificity and cancer. Three-dimensional culture assays provide a useful platform for dissecting these processes but, as discussed in a recent study in BMC Biology on the culture of mammary gland epithelial cells, multiple parameters that influence the model must be taken into account.
Date: January 21, 2010
Creator: Inman, J. L. & Bissell, Mina
System: The UNT Digital Library
APPLICATION OF A THIN FILM EVAPORATOR SYSTEM FOR MANAGEMENT OF LIQUID HIGH-LEVEL WASTES AT HANFORD (open access)

APPLICATION OF A THIN FILM EVAPORATOR SYSTEM FOR MANAGEMENT OF LIQUID HIGH-LEVEL WASTES AT HANFORD

A modular, transportable evaporator system, using thin film evaporative technology, is planned for deployment at the Hanford radioactive waste storage tank complex. This technology, herein referred to as a wiped film evaporator (WFE), will be located at grade level above an underground storage tank to receive pumped liquids, concentrate the liquid stream from 1.1 specific gravity to approximately 1.4 and then return the concentrated solution back into the tank. Water is removed by evaporation at an internal heated drum surface exposed to high vacuum. The condensed water stream will be shipped to the site effluent treatment facility for final disposal. This operation provides significant risk mitigation to failure of the aging 242-A Evaporator facility; the only operating evaporative system at Hanford maximizing waste storage. This technology is being implemented through a development and deployment project by the tank farm operating contractor, Washington River Protection Solutions (WRPS), for the Office of River Protection/Department of Energy (ORP/DOE), through Columbia Energy & Environmental Services, Inc. (Columbia Energy). The project will finalize technology maturity and install a system at one of the double-shell tank farms. This paper discusses results of pre-project pilot-scale testing by Columbia Energy and ongoing technology maturation development scope through fiscal …
Date: January 14, 2010
Creator: Tedeschi, A. R. & Wilson, R. A.
System: The UNT Digital Library
Approximation Properties of Coarse Spaces by Algebraic Multigrid (open access)

Approximation Properties of Coarse Spaces by Algebraic Multigrid

None
Date: January 14, 2010
Creator: Vassilevski, P. S.
System: The UNT Digital Library
The ArgoNeuT experiment (open access)

The ArgoNeuT experiment

ArgoNeuT is a Liquid Argon Time Projection Chamber neutrino experiment that recently completed its physics run in the NuMI beamline at Fermilab. Along with research and design for future LArTPCs, the experiments goals include performing a number of neutrino and anti-neutrino cross section measurements. Also, ArgoNeuT hopes to further the understanding of the nuclear physics involved in neutrino scattering by characterizing the low energy protons created in such interactions.
Date: January 1, 2010
Creator: Spitz, J. & U., /Yale
System: The UNT Digital Library
Assessing out-of-band flare effects at the wafer level for EUV lithography (open access)

Assessing out-of-band flare effects at the wafer level for EUV lithography

To accurately estimate the flare contribution from the out-of-band (OOB), the integration of a DUV source into the SEMATECH Berkeley 0.3-NA Micro-field Exposure tool is proposed, enabling precisely controlled exposures along with the EUV patterning of resists in vacuum. First measurements evaluating the impact of bandwidth selected exposures with a table-top set-up and subsequent EUV patterning show significant impact on line-edge roughness and process performance. We outline a simulation-based method for computing the effective flare from resist sensitive wavelengths as a function of mask pattern types and sizes. This simulation method is benchmarked against measured OOB flare measurements and the results obtained are in agreement.
Date: January 25, 2010
Creator: George, Simi; Naulleau, Patrick; Kemp, Charles; Denham, Paul & Rekawa, Senajith
System: The UNT Digital Library
Autoignition behavior of unsaturated hydrocarbons in the low and high temperature regions (open access)

Autoignition behavior of unsaturated hydrocarbons in the low and high temperature regions

None
Date: January 11, 2010
Creator: Mehl, M; Pitz, W J; Westbrook, C K; Yasunaga, K & Curran, H J
System: The UNT Digital Library
AUTOMATING GROUNDWATER SAMPLING AT HANFORD THE NEXT STEP (open access)

AUTOMATING GROUNDWATER SAMPLING AT HANFORD THE NEXT STEP

Historically, the groundwater monitoring activities at the Department of Energy's Hanford Site in southeastern Washington State have been very "people intensive." Approximately 1500 wells are sampled each year by field personnel or "samplers." These individuals have been issued pre-printed forms showing information about the well(s) for a particular sampling evolution. This information is taken from 2 official electronic databases: the Hanford Well information System (HWIS) and the Hanford Environmental Information System (HEIS). The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms in at the end of the day and other personnel posted the collected information onto a spreadsheet that was then printed and included in a log book. The log book was then used to make manual entries of the new information into the software application(s) for the HEIS and HWIS databases. A pilot project for automating this extremely tedious process was lauched in 2008. Initially, the automation was focused on water-level measurements. Now, the effort is being extended to automate the meta-data associated with collecting groundwater samples. The project allowed electronic forms produced in the field by samplers to be used in …
Date: January 21, 2010
Creator: CW, CONNELL; SF, CONLEY; RD, HILDEBRAND; DE, CUNNINGHAM; R_D_Doug_Hildebrand@rl.gov & DeVon_E_Cunningham@rl.gov
System: The UNT Digital Library
B baryon production and decays and B hadron lifetimes (open access)

B baryon production and decays and B hadron lifetimes

In this paper we review the most recent results concerning B Baryons at CDF and D0, including the observation and the study of the properties of the {Omega}{sub b}{sup -}, {Xi}{sub b}{sup -} and {Sigma}{sub b}{sup {+-}(*)}, the observation of new {Lambda}{sub b}{sup 0} decay modes, and a new measurement of the lifetime of the b hadrons in decays with a J/{Psi}. The {Omega}{sub b}{sup -} baryon is observed through the decay chain {Omega}{sub b}{sup -} {yields} J/{Psi}{Omega}{sup -}, where J/{Psi} {yields} {mu}{sup +}{mu}{sup -}, {Omega}{sup -} {yields} {Lambda}K{sup -}, and {Lambda} {yields} pK{sup -}, using 4.2 fb{sup -1} of data. The {Omega}{sub b}{sup -} mass is measured to be 6054.4 {+-} 6.8(stat.) {+-} 0.9(syst.) MeV/c{sup 2}, and the lifetime 1.13{sub -0.40}{sup +0.53}(stat.) {+-} 0.02(syst.) ps. For the {Xi}{sub b}{sup -} the mass is measured 5790.9 {+-} 2.6(stat.) {+-} 0.8(syst.) MeV/c{sup 2} and the lifetime 1.56{sub -0.25}{sup +0.27}(stat.) {+-} 0.02(syst.) ps. A new accurate measurement of the properties of the resonances {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}*{sub b}{sup +}, and {Sigma}*{sub b}{sup -} has been performed in 6 fb{sup -1} of data, and the masses have been determined, m({Sigma}{sub b}{sup +}) = 5811.2{sub -0.8}{sup +0.9}(stat.) {+-} 1.7(syst.), m({Sigma}{sub b}{sup …
Date: January 1, 2010
Creator: Donati, S.
System: The UNT Digital Library
Baryon spectroscopy results at the Tevatron (open access)

Baryon spectroscopy results at the Tevatron

The Tevatron at Fermilab continues to collect data at high luminosity resulting in datasets in excess of 6 fb{sup -1} of integrated luminosity. The high collision energies allow for the observation of new heavy quark baryon states not currently accessible at any other facility. In addition to the ground state {Lambda}{sub b}, the spectroscopy and properties of the new heavy baryon states {Omega}{sub b}, {Xi}{sub b}, and {Sigma}{sub b}{sup (*)} as measured by the CDF and D0 Collaborations are presented.
Date: January 1, 2010
Creator: Van Kooten, R.
System: The UNT Digital Library
Buoyancy effects on upward brine displacement caused by CO2 injection (open access)

Buoyancy effects on upward brine displacement caused by CO2 injection

Upward displacement of brine from deep reservoirs driven by pressure increases resulting from CO{sub 2} injection for geologic carbon sequestration may occur through improperly sealed abandoned wells, through permeable faults, or through permeable channels between pinch-outs of shale formations. The concern about upward brine flow is that, upon intrusion into aquifers containing groundwater resources, the brine may degrade groundwater. Because both salinity and temperature increase with depth in sedimentary basins, upward displacement of brine involves lifting fluid that is saline but also warm into shallower regions that contain fresher, cooler water. We have carried out dynamic simulations using TOUGH2/EOS7 of upward displacement of warm, salty water into cooler, fresher aquifers in a highly idealized two-dimensional model consisting of a vertical conduit (representing a well or permeable fault) connecting a deep and a shallow reservoir. Our simulations show that for small pressure increases and/or high-salinity-gradient cases, brine is pushed up the conduit to a new static steady-state equilibrium. On the other hand, if the pressure rise is large enough that brine is pushed up the conduit and into the overlying upper aquifer, flow may be sustained if the dense brine is allowed to spread laterally. In this scenario, dense brine only …
Date: January 15, 2010
Creator: Oldenburg, C.M. & Rinaldi, A.
System: The UNT Digital Library
Calibration of a High Resolution Soft X-ray Spectrometer (open access)

Calibration of a High Resolution Soft X-ray Spectrometer

A high resolution grating spectrometer (HRGS) with 2400 line/mm variable line spacing grating for the 10-50 {angstrom} wavelength range has been designed for laser-produced plasma experiments at the Lawrence Livermore National Laboratory (LLNL). The spectrometer has a large radius of curvature, R=44.3 m, is operated at a 2{sup o} grazing angle and can record high signal-to-noise spectra when used with a low-noise, cooled, charge-coupled device detector. The instrument can be operated with a 10-25 {micro}m wide slit to achieve the best spectral resolving power on laser plasma sources, approaching 2000, or in slitless mode with a small symmetrical emission source. Results will be presented for the spectral response of the spectrometer cross-calibrated at the LLNL Electron Beam Ion Trap facility using the broadband x-ray energy EBIT Calorimeter Spectrometer (ECS).
Date: January 26, 2010
Creator: Dunn, J; Beiersdorfer, P; Brown, G V & Magee, E W
System: The UNT Digital Library
Carrier heating in disordered conjugated polymers in electric field (open access)

Carrier heating in disordered conjugated polymers in electric field

The electric field dependence of charge carrier transport and the effect of carrier heating in disordered conjugated polymers were investigated. A parameter-free multiscale methodology consisting of classical molecular dynamics simulation for the generation of the atomic structure, large system electronic structure and electron-phonon coupling constants calculations and the procedure for extracting the bulk polymer mobility, was used. The results suggested that the mobility of a fully disordered poly(3-hexylthiophene) (P3HT) polymer increases with electric field which is consistent with the experimental results on samples of regiorandom P3HT and different from the results on more ordered regioregular P3HT polymers, where the opposite trend is often observed at low electric fields. We calculated the electric field dependence of the effective carrier temperature and showed however that the effective temperature cannot be used to replace the joint effect of temperature and electric field, in contrast to previous theoretical results from phenomenological models. Such a difference was traced to originate from the use of simplified Miller-Abrahams hopping rates in phenomenological models in contrast to our considerations that explicitly take into account the electronic state wave functions and the interaction with all phonon modes.
Date: January 26, 2010
Creator: Vukmirovic, Nenad & Wang, Lin-Wang
System: The UNT Digital Library
A Case for Including Transactions in OpenMP (open access)

A Case for Including Transactions in OpenMP

Transactional Memory (TM) has received significant attention recently as a mechanism to reduce the complexity of shared memory programming. We explore the potential of TM to improve OpenMP applications. We combine a software TM (STM) system to support transactions with an OpenMP implementation to start thread teams and provide task and loop-level parallelization. We apply this system to two application scenarios that reflect realistic TM use cases. Our results with this system demonstrate that even with the relatively high overheads of STM, transactions can outperform OpenMP critical sections by 10%. Overall, our study demonstrates that extending OpenMP to include transactions would ease programming effort while allowing improved performance.
Date: January 25, 2010
Creator: Wong, M.; Bihari, B. L.; de Supinski, B. R.; Wu, P.; Michael, M.; Liu, Y. et al.
System: The UNT Digital Library
CDF GlideinWMS usage in grid computing of high energy physics (open access)

CDF GlideinWMS usage in grid computing of high energy physics

Many members of large science collaborations already have specialized grids available to advance their research in the need of getting more computing resources for data analysis. This has forced the Collider Detector at Fermilab (CDF) collaboration to move beyond the usage of dedicated resources and start exploiting Grid resources. Nowadays, CDF experiment is increasingly relying on glidein-based computing pools for data reconstruction. Especially, Monte Carlo production and user data analysis, serving over 400 users by central analysis farm middleware (CAF) on the top of Condor batch system and CDF Grid infrastructure. Condor is designed as distributed architecture and its glidein mechanism of pilot jobs is ideal for abstracting the Grid computing by making a virtual private computing pool. We would like to present the first production use of the generic pilot-based Workload Management System (glideinWMS), which is an implementation of the pilot mechanism based on the Condor distributed infrastructure. CDF Grid computing uses glideinWMS for its data reconstruction on the FNAL campus Grid, user analysis and Monte Carlo production across Open Science Grid (OSG). We review this computing model and setup used including CDF specific configuration within the glideinWMS system which provides powerful scalability and makes Grid computing working like …
Date: January 1, 2010
Creator: Zvada, Marian; /Fermilab /Kosice, IEF; Benjamin, Doug; U., /Duke; Sfiligoi, Igor & /Fermilab
System: The UNT Digital Library
CDF software distribution on the grid using Parrot (open access)

CDF software distribution on the grid using Parrot

Large international collaborations that use decentralized computing models are becoming a custom rather than an exception in High Energy Physics. A good computing model for such big collaborations has to deal with the distribution of the experiment-specific software around the world. When the CDF experiment developed its software infrastructure, most computing was done on dedicated clusters. As a result, libraries, configuration files and large executables were deployed over a shared file system. In order to adapt its computing model to the Grid, CDF decided to distribute its software to all European Grid sites using Parrot, a user-level application capable of attaching existing programs to remote I/O systems through the filesystem interface. This choice allows CDF to use just one centralized source of code and a scalable set of caches all around Europe to efficiently distribute its code and requires almost no interaction with the existing Grid middleware or with local system administrators. This system has been in production at CDF in Europe since almost two years. Here, we present CDF implementation of Parrot and some comments on its performances.
Date: January 1, 2010
Creator: Compostella, G.; /INFN, CNAF; Pagan Griso, S.; U., /Padua; Lucchesi, D.; U., /Padua et al.
System: The UNT Digital Library
Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission (open access)

Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission

A relatively new technique for measuring the electron cloud density in storage rings has been developed and successfully demonstrated [S. De Santis, J.M. Byrd, F. Caspers, A. Krasnykh, T. Kroyer, M.T.F. Pivi, and K.G. Sonnad, Phys. Rev. Lett. 100, 094801 (2008).]. We present the experimental results of a systematic application of this technique at the Cornell Electron Storage Ring Test Accelerator. The technique is based on the phase modulation of the TE mode transmitted in a synchrotron beam pipe caused by the periodic variation of the density of electron plasma. Because of the relatively simple hardware requirements, this method has become increasingly popular and has been since successfully implemented in several machines. While the principles of this technique are straightforward, quantitative derivation of the electron cloud density from the measurement requires consideration of several effects, which we address in detail.
Date: January 2, 2010
Creator: De Santis, S.; Byrd, J. M.; Billing, M.; Palmer, M.; Sikora, J. & Carlson, B.
System: The UNT Digital Library
CMS centres worldwide: A new collaborative infrastructure (open access)

CMS centres worldwide: A new collaborative infrastructure

The CMS Experiment at the LHC is establishing a global network of inter-connected 'CMS Centres' for controls, operations and monitoring. These support: (1) CMS data quality monitoring, detector calibrations, and analysis; and (2) computing operations for the processing, storage and distribution of CMS data. We describe the infrastructure, computing, software, and communications systems required to create an effective and affordable CMS Centre. We present our highly successful operations experiences with the major CMS Centres at CERN, Fermilab, and DESY during the LHC first beam data-taking and cosmic ray commissioning work. The status of the various centres already operating or under construction in Asia, Europe, Russia, South America, and the USA is also described. We emphasise the collaborative communications aspects. For example, virtual co-location of experts in CMS Centres Worldwide is achieved using high-quality permanently-running 'telepresence' video links. Generic Web-based tools have been developed and deployed for monitoring, control, display management and outreach.
Date: January 1, 2010
Creator: Taylor, Lucas & Gottschalk, Erik
System: The UNT Digital Library
COG - Special Features of Interest to Criticality Safety Practitioners (open access)

COG - Special Features of Interest to Criticality Safety Practitioners

COG is a modern, general-purpose, high fidelity, multi-particle transport code developed at the Lawrence Livermore National Laboratory specifically for use in deep penetration (shielding) and criticality safety calculations. This paper describes some features in COG of special interest to criticality safety practitioners.
Date: January 14, 2010
Creator: Buck, R M; Heinrichs, D P; Krass, A W & Lent, E M
System: The UNT Digital Library
A collaborative network middleware project by Lambda Station, TeraPaths, and Phoebus (open access)

A collaborative network middleware project by Lambda Station, TeraPaths, and Phoebus

The TeraPaths, Lambda Station, and Phoebus projects, funded by the US Department of Energy, have successfully developed network middleware services that establish on-demand and manage true end-to-end, Quality-of-Service (QoS) aware, virtual network paths across multiple administrative network domains, select network paths and gracefully reroute traffic over these dynamic paths, and streamline traffic between packet and circuit networks using transparent gateways. These services improve network QoS and performance for applications, playing a critical role in the effective use of emerging dynamic circuit network services. They provide interfaces to applications, such as dCache SRM, translate network service requests into network device configurations, and coordinate with each other to setup up end-to-end network paths. The End Site Control Plane Subsystem (ESCPS) builds upon the success of the three projects by combining their individual capabilities into the next generation of network middleware. ESCPS addresses challenges such as cross-domain control plane signalling and interoperability, authentication and authorization in a Grid environment, topology discovery, and dynamic status tracking. The new network middleware will take full advantage of the perfSONAR monitoring infrastructure and the Inter-Domain Control plane efforts and will be deployed and fully vetted in the Large Hadron Collider data movement environment.
Date: January 1, 2010
Creator: Bobyshev, A.; /Fermilab; Bradley, S.; /Brookhaven; Crawford, M.; /Fermilab et al.
System: The UNT Digital Library
Commissioning of the Cryogenics of the LHC Long Straight Sections (open access)

Commissioning of the Cryogenics of the LHC Long Straight Sections

The LHC is made of eight circular arcs interspaced with eight Long Straight Sections (LSS). Most powering interfaces to the LHC are located in these sections where the particle beams are focused and shaped for collision, cleaning and acceleration. The LSSs are constituted of several unique cryogenic devices and systems like electrical feed-boxes, standalone superconducting magnets, superconducting links, RF cavities and final focusing superconducting magnets. This paper presents the cryogenic commissioning and the main results obtained during the first operation of the LHC Long Straight Sections.
Date: January 1, 2010
Creator: Perin, A.; Casas-Cubillos, J.; Claudet, S.; Darve, C.; Ferlin, G.; Millet, F. et al.
System: The UNT Digital Library
Comparison Between Nb3Al and Nb3Sn Strands and Cables for High Field Accelerator Magnets (open access)

Comparison Between Nb3Al and Nb3Sn Strands and Cables for High Field Accelerator Magnets

The Nb{sub 3}Al small racetrack magnet, SR07, has been successfully built and tested to its short sample limit beyond 10 Tesla without any training. Thus the practical application of Nb{sub 3}Al strands for high field accelerator magnets is established. The characteristics of the representative F4 strand and cable, are compared with the typical Nb{sub 3}Sn strand and cable. It is represented by the OST high current RRP Nb{sub 3}Sn strand with 108/127 configuration. The effects of Rutherford cabling to both type strands are explained and the inherent problem of the Nb{sub 3}Sn strand is discussed. Also the test results of two representative small racetrack magnets are compared from the stand point of Ic values, and training. The maximum current density of the Nb{sub 3}Al strands is still smaller than that of the Nb{sub 3}Sn strands, but if we take into account of the stress-strain characteristics, Nb{sub 3}Al strands become somewhat favorable in some applications.
Date: January 1, 2010
Creator: Yamada, R.; Kikuchi, A.; Barzi, E.; Chlachidze, G.; Rusy, A.; Takeuchi, T. et al.
System: The UNT Digital Library