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Ferromagnetism in GaN: Gd: A density functional theory study

Description: First principle calculations of the electronic structure and magnetic interaction of GaN:Gd have been performed within the Generalized Gradient Approximation (GGA) of the density functional theory (DFT) with the on-site Coulomb energy U taken into account (also referred to as GGA+U). The ferromagnetic p-d coupling is found to be over two orders of magnitude larger than the s-d exchange coupling. The experimental colossal magnetic moments and room temperature ferromagnetism in GaN:Gd reported re… more
Date: February 4, 2008
Creator: Stevenson, Cynthia & Stevenson, Cynthia
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of the Fast Focusing DIRC (fDIRC)

Description: We have built and successfully tested a novel particle identification detector concept, the Fast Focusing DIRC (fDIRC). The prototype's concept is based on the BaBar DIRC with several important improvements: (a) much faster pixelated photon detectors based on Burle MCP-PMTs and Hamamatsu MaPMTs, (b) a focusing mirror allowing a smaller photon detector, reducing the sensitivity to backgrounds in future applications, (c) electronics capable of measuring the single photon resolution to better than… more
Date: February 4, 2008
Creator: Benitez, J.; Leith, D. W. G. S.; Mazaheri, G.; Ratcliff, B. N.; Schwiening, J.; Vavra, J. et al.
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Partner: UNT Libraries Government Documents Department
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Ultrafast high strain rate acoustic wave measurements at high static pressure in a diamond anvil cell

Description: We have used sub-picosecond laser pulses to launch ultra-high strain rate ({approx} 10{sup 9} s{sup -1}) nonlinear acoustic waves into a 4:1 methanol-ethanol pressure medium which has been precompressed in a standard diamond anvil cell. Using ultrafast interferometry, we have characterized acoustic wave propagation into the pressure medium at static compression up to 24 GPa. We find that the velocity is dependent on the incident laser fluence, demonstrating a nonlinear acoustic response which m… more
Date: February 4, 2008
Creator: Armstrong, M; Crowhurst, J; Reed, E & Zaug, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Parallel 3D Finite Element Numerical Modelling of DC Electron Guns

Description: In this paper we present Gun3P, a parallel 3D finite element application that the Advanced Computations Department at the Stanford Linear Accelerator Center is developing for the analysis of beam formation in DC guns and beam transport in klystrons. Gun3P is targeted specially to complex geometries that cannot be described by 2D models and cannot be easily handled by finite difference discretizations. Its parallel capability allows simulations with more accuracy and less processing time than pa… more
Date: February 4, 2008
Creator: Prudencio, E.; Candel, A.; Ge, L.; Kabel, A.; Ko, K.; Lee, L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AdS/CFT and Light-Front QCD

Description: The AdS/CFT correspondence between string theory in AdS space and conformal field theories in physical space-time leads to an analytic, semi-classical model for strongly-coupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. The AdS/CFT correspondence also provides insights into the inherently nonperturbative aspects of QCD such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular… more
Date: February 4, 2008
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prototype performance of novel muon telescope detector at STAR

Description: Research on a large-area, cost-effective Muon Telescope Detector has been carried out for RHIC and for next generation detectors at future QCD Lab. We utilize state-of-the-art multi-gap resistive plate chambers with large modules and long readout strips in detector design [l]. The results from cosmic ray and beam test will be presented to address intrinsic timing and spatial resolution for a Long-MRF'C. The prototype performance of a novel muon telescope detector at STAR will be reported, inclu… more
Date: February 4, 2008
Creator: Ruan,L. & Ames, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Multiplexed Diagnostic Platform for Point-of-Care Pathogen Detection

Description: We developed an automated point-of-care diagnostic instrument that is capable of analyzing nasal swab samples for the presence of respiratory diseases. This robust instrument, called FluIDx, performs autonomous multiplexed RT-PCR reactions that are analyzed by microsphere xMAP technology. We evaluated the performance of FluIDx, in comparison rapid tests specific for influenza and respiratory syncytial virus, in a clinical study performed at the UC Davis Medical Center. The clinical study includ… more
Date: February 4, 2008
Creator: Regan, J. F.; Letant, S. E.; Adams, K. L.; Mahnke, R. C.; Nguyen, N. T.; Dzenitis, J. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compact MEMS-based Adaptive Optics Optical Coherence Tomography for Clinical Use

Description: We describe a compact MEMS-based adaptive optics (AO) optical coherence tomography system with improved AO performance and ease of clinical use. A typical AO system consists of a Shack-Hartmann wavefront sensor and a deformable mirror that measures and corrects the ocular and system aberrations. Because of the limitation on the current deformable mirror technologies, the amount of real-time ocular-aberration compensation is restricted and small in the previous AO-OCT instruments. In this instru… more
Date: February 4, 2008
Creator: Chen, D.; Olivier, S.; Jones, S.; Zawadzki, R.; Evans, J.; Choi, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scaling Behavior of the First Arrival Time of a Random-Walking Magnetic Domain

Description: We report a universal scaling behavior of the first arrival time of a traveling magnetic domain wall into a finite space-time observation window of a magneto-optical microscope enabling direct visualization of a Barkhausen avalanche in real time. The first arrival time of the traveling magnetic domain wall exhibits a nontrivial fluctuation and its statistical distribution is described by universal power-law scaling with scaling exponents of 1.34 {+-} 0.07 for CoCr and CoCrPt films, despite thei… more
Date: February 4, 2008
Creator: Im, M. Y.; Lee, S. H.; Kim, D. H.; Fischer, P. & Shin, S. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Difference Imaging of Lensed Quasar Candidates in the SDSS Supernova Survey Region

Description: Difference imaging provides a new way to discover gravitationally lensed quasars because few non-lensed sources will show spatially extended, time variable flux. We test the method on lens candidates in the Sloan Digital Sky Survey (SDSS) Supernova Survey region from the SDSS Quasar Lens Search (SQLS) and their surrounding fields. Starting from 20768 sources, including 49 SDSS quasars and 36 candidate lenses/lensed images, we find that 21 sources including 15 SDSS QSOs and 7 candidate lenses/le… more
Date: February 4, 2008
Creator: Lacki, Brian C.; Kochanek, Christopher S.; Stanek, Krzysztof Z.; Inada, Naohisa & Oguri, Masamune
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evidence for Color Transparency and Direct Hadron Production at RHIC

Description: The QCD color transparency of higher-twist contributions to the inclusive hadroproduction cross section, where the trigger proton is produced directly in a short-distance subprocess, can explain several remarkable features of high-p{sub T} proton production in heavy ion collisions which have recently been observed at RHIC: (a) the anomalous increase of the p {yields} {pi} ratio with centrality (b): the more rapid power-law fall-off at fixed x{sub T} = 2p{sub T}/{radical}s of the charged particl… more
Date: February 4, 2008
Creator: Brodsky, S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Semileptonic B Decays in BaBar

Description: Recent results from BABAR on the determination of the CKM matrix elements |V{sub cb}| and |V{sub ub}| are presented.
Date: February 4, 2008
Creator: Sacco, R. & /Queen Mary, U. of London
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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INNOVATIVE TECHNIQUES AND TECHNOLOGY APPLICATION IN MANAGEMENT OF REMOTE HANDLED AND LARGE SIZED MIXED WASTE FORMS

Description: CH2M HILL Hanford Group, Inc. (CH2M HILL) plays a critical role in Hanford Site cleanup for the U. S. Department of Energy, Office of River Protection (ORP). CH2M HILL is responsible for the management of 177 tanks containing 53 million gallons of highly radioactive wastes generated from weapons production activities from 1943 through 1990. In that time, 149 single-shell tanks, ranging in capacity from 50,000 gallons to 500,000 gallons, and 28 double-shell tanks with a capacity of 1 million gal… more
Date: February 4, 2008
Creator: LT, BLACKFORD
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Partner: UNT Libraries Government Documents Department
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A Gravity Dual of Metastable Dynamical Supersymmetry Breaking

Description: Metastable, supersymmetry-breaking configurations can be created in flux geometries by placing antibranes in warped throats. Via gauge/gravity duality, such configurations should have an interpretation as supersymmetry-breaking states in the dual field theory. In this paper, we perturbatively determine the asymptotic supergravity solutions corresponding to D3-brane probes placed at the tip of the cascading warped deformed conifold geometry, which is dual to an SU(N+M) x SU(N) gauge theory. The … more
Date: February 4, 2008
Creator: DeWolfe, Oliver; U., /Colorado; Kachru, Shamit; Mulligan, Michael & /Stanford U., Phys. Dept. /SLAC
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Direct Functionalization of Nitrogen Heterocycles via Rh-Catalyzed C-H Bond Activation

Description: Nitrogen heterocycles are present in many compounds of enormous practical importance, ranging from pharmaceutical agents and biological probes to electroactive materials. Direct funtionalization of nitrogen heterocycles through C-H bond activation constitutes a powerful means of regioselectively introducing a variety of substituents with diverse functional groups onto the heterocycle scaffold. Working together, our two groups have developed a family of Rh-catalyzed heterocycle alkylation and ar… more
Date: February 4, 2008
Creator: Lewis, Jared; Bergman, Robert & Ellman, Jonathan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Further improvement in the precision of 233U measurements by accelerator mass spectrometry at the Lawrence Livermore National Laboratory.

Description: In response to sponsor interest in October 2005 we proposed two methods for enhancing the precision of {sup 233}U accelerator mass spectrometry (AMS) capabilities at the Lawrence Livermore National Laboratory (LLNL). In a previous report we evaluated the first method and demonstrated that by increasing sample loading by a factor of four coupled with performing four replicates of each sample, we could achieve measurement precision of {approx}1%. Recent modifications to our system have enabled us… more
Date: February 4, 2008
Creator: Tumey, S. J.; Brown, T. A.; Hamilton, T. F. & Buchholz, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental and Numerical Investigations of Soil Desiccation for Vadose Zone Remediation: Report for Fiscal Year 2007

Description: Apart from source excavation, the options available for the remediation of vadose zone metal and radionuclide contaminants beyond the practical excavation depth (0 to 15 m) are quite limited. Of the available technologies, very few are applicable to the deep vadose zone with the top-ranked candidate being soil desiccation. An expert panel review of the work on infiltration control and supplemental technologies identified a number of knowledge gaps that would need to be overcome before soil desi… more
Date: February 4, 2008
Creator: Ward, Andy L.; Oostrom, Mart & Bacon, Diana H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trace Anomaly and Dimension Two Gluon Condensate Above the Phase Transition

Description: The dimension two gluon condensate has been used previously within a simple phenomenological model to describe power corrections from available lattice data for the renormalized Polyakov loop and the heavy quark-antiquark free energy in the deconfined phase of QCD. The QCD trace anomaly of gluodynamics also shows unequivocal inverse temperature power corrections which may be encoded as dimension two gluon condensate. We analyze lattice data of the trace anomaly and compare with other determinat… more
Date: February 4, 2008
Creator: Megias,E.; Ruiz Arriola, E. & Salcedo, L.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electromagnetic Pulses at Short-Pulse Laser Facilities

Description: Electromagnetic Pulse (EMP) is a known issue for short-pulse laser facilities, and will also be an issue for experiments using the advanced radiographic capability (ARC) at the National Ignition Facility (NIF). The ARC diagnostic uses four NIF beams that are compressed to picosecond durations for backlighting ignition capsules and other applications. Consequently, we are working to understand the EMP due to high-energy (MeV) electrons escaping from targets heated by short-pulse lasers. Our appr… more
Date: February 4, 2008
Creator: Brown, C G; Throop, A; Eder, D & Kimbrough, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Residence Restrictions for Released Sex Offenders

Description: This report analyzes the issue of residence restriction laws for released sex offenders by briefly examining provisions of the Adam Walsh Act; identifying and comparing residence restriction laws in a number of states; discussing the impact of residence restriction laws on sex offenders, law enforcement and the public; presenting arguments in support of and against residence restriction laws; and reviewing some alternative proposals for monitoring released sex offenders..
Date: February 4, 2008
Creator: Laney, Garrine P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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China Naval Modernization: Implications for U.S. Navy Capabilities — Background and Issues for Congress

Description: This report outlines the growing concern in Congress and elsewhere about China's military modernization. The topic is an increasing factor in discussions over future required U.S. Navy capabilities. The issue for Congress addressed in this report is: How should China's military modernization be factored into decisions about U.S. Navy programs?
Date: February 4, 2008
Creator: O'Rourke, Ronald
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent results rom BRAHMS

Description: The BRAHMS collaboration ended its data collection program in 2006. We are now well advanced in the analysis of a comprehensive set of data that spans systems ranging in mass from p+p to Au+Au and in energy from {radical}{ovr {sup S}N N} = 62.4 to 200 GeV. Our analysis has taken two distinct paths: we explore the rapidity dependence of intermediate and high-transverse-momentum, identified-particle production, thus helping to characterize the strongly-interacting quark-gluon plasma (sQGP) formed… more
Date: February 4, 2008
Creator: Debbe,R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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From AGS-SPS and Onwards to the LHC

Description: The author reviews the history of the efforts using heavy ion collisions to make new forms of matter. Both the development of the theoretical ideas about such new forms of matter, and as well the past, present and planned experimental efforts are discussed. The development of this activity in both India and China are highlighted.
Date: February 4, 2008
Creator: McLerran, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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