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Arizona Border Surveillance Technology: More Information on Plans and Costs Is Needed before Proceeding

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In recent years, nearly half of all annual apprehensions of illegal aliens along the entire Southwest border with Mexico have occurred along the Arizona border. Keeping illegal flows of people and drugs under control remains a top priority for the Department of Homeland Security's (DHS) U.S. Customs and Border Protection (CBP). In 2005, the Secure Border Initiative Network (SBInet) was conceived as a su… more
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Vacant Properties: Growing Number Increases Communities' Costs and Challenges

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Vacant and unattended residential properties can attract crime, cause blight, and pose a threat to public safety. While homeowners or mortgage owners--including the mortgage servicers that administer loans on behalf of loan owners--are responsible for maintaining vacant properties with mortgages undergoing foreclosure, the costs local governments incur to mitigate any unsafe conditions can be significan… more
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Federal Courthouse Construction: Nationwide Space and Cost Issues Are Applicable to L.A. Courthouse Project

Description: Testimony issued by the Government Accountability Office with an abstract that begins "In 2000, as part of a multibillion-dollar courthouse construction initiative, the judiciary requested and the General Services Administration (GSA) proposed building a new courthouse in Los Angeles to increase security, efficiency, and space--but construction never began. About $400 million was appropriated for the L.A. courthouse project. For this testimony, GAO was asked to report on (1) the status of the L… more
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Initial Pilot Training: Better Management Controls Are Needed to Improve FAA Oversight

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Regional airlines have experienced the last six fatal commercial airline accidents, and pilot performance has been cited as a potential contributory factor in four of these accidents. As a result, Congress and others have raised questions about, among other issues, the initial pilot education and training required before pilots can be hired by airlines, at which time they receive further training. The i… more
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simplifying Multi-Jet QCD Computation

Description: These lectures give a pedagogical discussion of the computation of QCD tree amplitudes for collider physics. The tools reviewed are spinor products, color ordering, MHV amplitudes, and the Britto-Cachazo-Feng-Witten recursion formula.
Date: November 4, 2011
Creator: Peskin, Michael E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Quarkonium Spectroscopy And Search for New States at BaBar

Description: The BaBar experiment at the PEP-II B-factory gives excellent opportunities for the quarkonium spectroscopy. Investigation of the properties of new states like the X(3872), Y(3940) and Y(4260) are performed aiming to understand their nature. Recent BaBar results will be presented in this paper. At the B-factories charmonium and charmonium-like states are copiously produced via several mechanisms: in B decay (color suppressed b {yields} c transition), double charmonium production (e{sup +}e{sup -… more
Date: November 4, 2011
Creator: Cibinetto, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Copper Prototype Measurements of the HOM, LOM And SOM Couplers for the ILC Crab Cavity

Description: The ILC Crab Cavity is positioned close to the IP and delivered luminosity is very sensitive to the wakefields induced in it by the beam. A set of couplers were designed to couple to and damp the spurious modes of the crab cavity. As the crab cavity operates using a dipole mode, it has different damping requirements from an accelerating cavity. A separate coupler is required for the monopole modes below the operating frequency of 3.9 GHz (known as the LOMs), the opposite polarization of the ope… more
Date: November 4, 2011
Creator: Burt, G.; Ambattu, P.K.; Dexter, A.C.; U., /Lancaster; Bellantoni, L.; /Fermilab et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Status of High Power Tests of Normal Conducting Single-Cell Structures

Description: We report the results of ongoing high power tests of single-cell standing wave structures. These tests are part of an experimental and theoretical study of rf breakdown in normal conducting structures at 11.4 GHz. The goal of this study is to determine the maximum gradient possibilities for normal-conducting rf powered particle beam accelerators. The test setup consists of reusable mode launchers and short test structures powered by SLACs XL-4 klystron. The mode launchers and structures were ma… more
Date: November 4, 2011
Creator: Dolgashev, V. A.; Tantawi, S. G.; Higashi, Y. & Higo, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Sensible Heat, Direct, Dual-Media Thermal Energy Storagy System: Phase 1 Final Technical Report

Description: Work under this project has ultimately focused on the development of a modular packed bed based thermal energy storage system. The design assumes the use of standard segments of carbon steel pipe filled with spherical materials creating a packed bed. These materials are assumed to be manufactured in such a way that the spherical shape is uniform throughout the packed bed. Out of 32 candidate materials evaluated, 8 materials remain. Each material meets the Phase I milestones that were specified … more
Date: November 4, 2011
Creator: Newmarker, Marc & Campbell, Mark
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Experimental Study of Synchro-Betatron Coupling Induced By Dipole Modulation

Description: Synchro-betatron coupling in a proton storage ring with electron cooling was studied experimentally by modulating a transverse dipole field close to the synchrotron frequency. The combination of the electron cooling and transverse field modulation on the synchrotron oscillation is equivalent to a dissipative parametric resonant system. The proton bunch was observed to split longitudinally into two pieces, or beamlets, converging toward attractors of the dissipative system. These phenomena might… more
Date: November 4, 2011
Creator: Syphers, M.; Ball, M.; Brabson, B.; Budnick, J.; Caussyn, D. D.; Chao, A. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Observations and Modeling of Debris and Shrapnel Impacts on Optics and Diagnostics at the National Ignition Facility

Description: A wide range of targets with laser energies spanning two orders of magnitude have been shot at the National Ignition Facility (NIF). The National Ignition Campaign (NIC) targets are cryogenic with Si supports and cooling rings attached to an Al thermo-mechanical package (TMP) with a thin (30 micron) Au hohlraum inside. Particular attention is placed on the low-energy shots where the TMP is not completely vaporized. In addition to NIC targets, a range of other targets has also been fielded on NI… more
Date: November 4, 2011
Creator: Eder, D.; Bailey, D.; Chamgers, F.; Darnell, I.; Nicola, P. D.; Dixit, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent Upgrade of the Klystron Modulator at SLAC

Description: The SLAC National Accelerator Laboratory employs 244 klystron modulators on its two-mile-long linear accelerator that has been operational since the early days of the SLAC establishment in the sixties. Each of these original modulators was designed to provide 250 kV, 262 A and 3.5 {mu}S at up to 360 pps using an inductance-capacitance resonant charging system, a modified type-E pulse-forming network (PFN), and a pulse transformer. The modulator internal control comprised of large step-start res… more
Date: November 4, 2011
Creator: Nguyen, M. N.; Burkhart, C. P.; Lam, B. K. & Morris, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Scattering Amplitudes: The Most Perfect Microscopic Structures in the Universe

Description: This article gives an overview of many of the recent developments in understanding the structure of relativistic scattering amplitudes in gauge theories ranging from QCD to N = 4 super-Yang-Mills theory, as well as (super)gravity. I also provide a pedagogical introduction to some of the basic tools used to organize and illuminate the color and kinematic structure of amplitudes. This article is an invited review introducing a special issue of Journal of Physics A devoted to 'Scattering Amplitude… more
Date: November 4, 2011
Creator: Dixon, Lance J. & /SLAC, /CERN
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Design of the Positron Source for the International Linear Collider

Description: The high luminosity requirements and the option of a polarized positron beam present a great challenge for the positron source of a future linear collider. This paper provides a comprehensive overview of the latest proposed design for the baseline positron source of the International Linear Collider (ILC). We report on recent progress and results concerning the main components of the source: including the undulator, capture optics, and target.
Date: November 4, 2011
Creator: Clarke, J. A.; Malyshev, O. B.; Scott, D. J.; Bailey, I. R.; Dainton, J. B.; Hock, K. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Study for ILC Damping Ring at KEKB

Description: ILC damping ring consists of very low emittance electron and positron storage rings. It is necessary for ILC damping ring to study electron cloud effects in such low emittance positron ring. We propose a low emittance operation of KEKB to study the effects.
Date: November 4, 2011
Creator: Flanagan, J. W.; Fukuma, H.; Kanazawa, K. I.; Koiso, H.; Masuzawa, M.; Ohmi, Kazuhito et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Reducing Memory Cost of Exact Diagonalization using Singular Value Decomposition

Description: We present a modified Lanczos algorithm to diagonalize lattice Hamiltonians with dramatically reduced memory requirements. The lattice of size N is partitioned into two subclusters. At each iteration the Lanczos vector is projected into a set of n{sub svd} smaller subcluster vectors using singular value decomposition. For low entanglement entropy S{sub ee}, (satisfied by short range Hamiltonians), we expect the truncation error to vanish as exp(-n{sup 1/S{sub ee}}{sub svd}). Convergence is test… more
Date: November 4, 2011
Creator: Weinstein, Marvin; Auerbach, Assa & Chandra, V. Ravi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Status of the Linac Coherent Light Source

Description: The Linac Coherent Light Source (LCLS) is a free electron laser facility in construction at Stanford Linear Accelerator Center. It is designed to operate in the wavelength range 0.15-1.5 nanometers. At the time of this conference, civil construction of new tunnels and buildings is complete, the necessary modifications to the SLAC linac are complete, and the undulator system and x-ray optics/diagnostics are being installed. The electron gun, 135 MeV injector linac and 250 MeV bunch compressor we… more
Date: November 4, 2011
Creator: Galayda, John N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Evolved QCD predictions for the meson-photon transition form factors: beyond the semiclassical AdS/QCD approximation

Description: The QCD evolution of the pion distribution amplitude (DA) {phi}{sub {pi}} (x, Q{sup 2}) is computed for several commonly used models. Our analysis includes the nonperturbative form predicted by lightfront holographic QCD, thus combining the nonperturbative bound state dynamics of the pion with the perturbative ERBL evolution of the pion distribution amplitude. We calculate the meson-photon transition form factors for the {pi}{sup 0}, {eta} and {eta}' using the hard-scattering formalism. We poin… more
Date: November 4, 2011
Creator: Brodsky, Stanley J.; /SLAC; Cao, Fu-Guang; U., /Massey U. /Beijing Normal; de Teramond, Guy F. & U., /Costa Rica
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The one-loop six-dimensional hexagon integral with three massive corners

Description: We compute the six-dimensional hexagon integral with three non-adjacent external masses analytically. After a simple rescaling, it is given by a function of six dual conformally invariant cross-ratios. The result can be expressed as a sum of 24 terms involving only one basic function, which is a simple linear combination of logarithms, dilogarithms, and trilogarithms of uniform degree three transcendentality. Our method uses differential equations to determine the symbol of the function, and an… more
Date: November 4, 2011
Creator: Del Duca, Vittorio; Dixon, Lance J.; Drummond, James M.; Duhr, Claude; Henn, Johannes M. & Smirnov, Vladimir A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

TANK 18 AND 19-F TIER 1A EQUIPMENT FILL MOCK UP TEST SUMMARY

Description: The United States Department of Energy (US DOE) has determined that Tanks 18-F and 19-F have met the F-Tank Farm (FTF) General Closure Plan Requirements and are ready to be permanently closed. The high-level waste (HLW) tanks have been isolated from FTF facilities. To complete operational closure they will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) discouraging future intrusion, and (4) providi… more
Date: November 4, 2011
Creator: Stefanko, D. & Langton, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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