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Application of the Principle of Maximum Conformality to the Top-Quark Forward-Backward Asymmetry at the Tevatron (open access)

Application of the Principle of Maximum Conformality to the Top-Quark Forward-Backward Asymmetry at the Tevatron

The renormalization scale uncertainty can be eliminated by the Principle of Maximum Conformality (PMC) in a systematic scheme-independent way. Applying the PMC for the t{bar t}-pair hadroproduction at the NNLO level, we have found that the total cross-sections {sigma}{sub t{bar t}} at both the Tevatron and LHC remain almost unchanged when taking very disparate initial scales {mu}{sub R}{sup init} equal to m{sub t}, 10 m{sub t}, 20 m{sub t} and {radical}s, which is consistent with renormalization group invariance. As an important new application, we apply PMC scale-setting to study the top-quark forward-backward asymmetry. We observe that the more convergent perturbative series after PMC scale-setting leads to a more accurate top-quark forward-backward asymmetry. The resulting PMC prediction on the asymmetry is also free from the initial renormalization scale-dependence. Because the NLO PMC scale has a dip behavior for the (q{bar q})-channel at small subprocess collision energies, the importance of this channel to the asymmetry is increased. We observe that the asymmetries A{sub FB}{sup t{bar t}} and A{sub FB}{sup p{bar p}} at the Tevatron will be increased by 42% in comparison to the previous estimates obtained by using conventional scale-setting; i.e. we obtain A{sub FB}{sup t{bar t}PMC} {approx_equal} 12.5% and A{sub FB}{sup …
Date: May 14, 2012
Creator: Brodsky, Stanley J. & Wu, Xing-Gang
Object Type: Article
System: The UNT Digital Library
Bahrain: Reform, Security, and U.S. Policy (open access)

Bahrain: Reform, Security, and U.S. Policy

The uprising that began in Bahrain on February 14, 2011, following the revolt that overthrew Egypt's President Hosni Mubarak three days earlier, began a political crisis that defies resolution. The ongoing unrest demonstrates that the grievances of the Shiite majority over the distribution of power and economic opportunities were not satisfied by prior efforts. The bulk of the Shiite majority in Bahrain says it demands a constitutional monarchy in which an elected parliament produces the government, but the Sunni minority believes the Shiites want nothing less than outright rule. This report looks at Bahrain's recent and current relationship with the U.S. and reasons for the unrest relating to socioeconomic issues.
Date: May 14, 2012
Creator: Katzman, Kenneth
Object Type: Report
System: The UNT Digital Library
Carbon Capture and Sequestration (CCS): A Primer (open access)

Carbon Capture and Sequestration (CCS): A Primer

This report is a brief summary of what CCS is, how it is supposed to work, why it has gained the interest and support of some members of Congress, and what some of the challenges are to its implementation and deployment across the United States.
Date: May 14, 2012
Creator: Folger, Peter
Object Type: Report
System: The UNT Digital Library
CDP - Adaptive Supervisory Control and Data Acquisition (SCADA) Technology for Infrastructure Protection (open access)

CDP - Adaptive Supervisory Control and Data Acquisition (SCADA) Technology for Infrastructure Protection

Supervisory Control and Data Acquisition (SCADA) Systems are a type of Industrial Control System characterized by the centralized (or hierarchical) monitoring and control of geographically dispersed assets. SCADA systems combine acquisition and network components to provide data gathering, transmission, and visualization for centralized monitoring and control. However these integrated capabilities, especially when built over legacy systems and protocols, generally result in vulnerabilities that can be exploited by attackers, with potentially disastrous consequences. Our research project proposal was to investigate new approaches for secure and survivable SCADA systems. In particular, we were interested in the resilience and adaptability of large-scale mission-critical monitoring and control infrastructures. Our research proposal was divided in two main tasks. The first task was centered on the design and investigation of algorithms for survivable SCADA systems and a prototype framework demonstration. The second task was centered on the characterization and demonstration of the proposed approach in illustrative scenarios (simulated or emulated).
Date: May 14, 2012
Creator: Carvalho, Marco & Ford, Richard
Object Type: Report
System: The UNT Digital Library
The Conceptional Design of the Shielding Layout and Beam Absorber at the PXIE (open access)

The Conceptional Design of the Shielding Layout and Beam Absorber at the PXIE

Project X is a high intensity proton facility conceived to support a world-leading physics program at Fermilab. Project X will provide high intensity beams for neutrino, kaon, muon, and nuclei based experiments and for studies supporting energy applications. The Project X Injector Experiment (PIXIE) is a prototype of the Project X front end. A 30 MeV 50 kW beam will be used to validate the design concept of the Project X. This paper discusses a design of the accelerator enclosure radiation shielding and the beam dump.
Date: May 14, 2012
Creator: Eidelman, Yu.; Kerby, J.; Lebedev, V.; Leibfritz, J.; Leveling, T.; Nagaisev, S. et al.
Object Type: Article
System: The UNT Digital Library
Congressional Oversight of Intelligence: Current Structure and Alternatives (open access)

Congressional Oversight of Intelligence: Current Structure and Alternatives

This report describes the current select committees on intelligence; characteristics and a model for a possible joint committee; recent actions by Congress; and obstacles affecting legislative oversight in the field.
Date: May 14, 2012
Creator: Halchin, L. Elaine & Kaiser, Frederick M.
Object Type: Report
System: The UNT Digital Library
Design Considerations for an MEBT Chopper Absorber of 2.1 MeV H- at the Project X Injector Experiment at Fermilab (open access)

Design Considerations for an MEBT Chopper Absorber of 2.1 MeV H- at the Project X Injector Experiment at Fermilab

The Project X Injector Experiment (PIXIE) will be a prototype of the Project X front end that will be used to validate the design concept and decrease technical risks. One of the most challenging components of PIXIE is the wide-band chopping system of the Medium Energy Beam Transport (MEBT) section, which will form an arbitrary bunch pattern from the initially CW 162.5 MHz 5mA beam. The present scenario assumes diverting 80% of the beam to an absorber to provide a beam with the average current of 1mA to SRF linac. This absorber must withstand a high level of energy deposition and high ion fluence, while being positioned in proximity of the superconductive cavities. This paper discusses design considerations for the absorber. Thermal and mechanical analyses of a conceptual design are presented, and future plans for the fabrication and testing of a prototype are described.
Date: May 14, 2012
Creator: Baffes, C.; Awida, M.; Chen, A.; Eidelman, Y.; Lebedev, V.; Prost, L. et al.
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF NEW MID-INFRARED ULTRAFAST LASER SOURCES FOR COMPACT COHERENT X-RAY SOURCES (open access)

DEVELOPMENT OF NEW MID-INFRARED ULTRAFAST LASER SOURCES FOR COMPACT COHERENT X-RAY SOURCES

In this project, we proposed to develop laser based mid-infrared lasers as a potentially robust and reliable source of ultrafast pulses in the mid-infrared region of the spectrum, and to apply this light source to generating bright, coherent, femtosecond-to-attosecond x-ray beams.
Date: May 14, 2012
Creator: Backus, Sterling
Object Type: Report
System: The UNT Digital Library
Drift time variations in CdZnTe detectors measured with alpha-particles: Their correlation with the detector’s responses (open access)

Drift time variations in CdZnTe detectors measured with alpha-particles: Their correlation with the detector’s responses

Homogeneity of properties related to material crystallinity is a critical parameter for achieving high-performance CdZnTe (CZT) radiation detectors. Unfortunately, this requirement is not always satisfied in today's commercial CZT material due to high concentrations of extended defects, in particular subgrain boundaries, which are believed to be part of the causes hampering the energy resolution and efficiency of CZT detectors. In the past, the effects of subgrain boundaries have been studied in Si, Ge and other semiconductors. It was demonstrated that subgrain boundaries tend to accumulate secondary phases and impurities causing inhomogeneous distributions of trapping centers. It was also demonstrated that subgrain boundaries result in local perturbations of the electric field, which affect the carrier transport and other properties of semiconductor devices. The subgrain boundaries in CZT material likely behave in a similar way, which makes them responsible for variations in the electron drift time and carrier trapping in CZT detectors. In this work, we employed the transient current technique to measure variations in the electron drift time and related the variations to the device performances and subgrain boundaries, whose presence in the crystals were confirmed with white beam X-ray diffraction topography and infrared transmission microscopy.
Date: May 14, 2012
Creator: E., Bolotnikov A.; Butcher, J.; Hamade, M.; Petryk, M.; Bolotnikov, A.; Camarda, G. et al.
Object Type: Article
System: The UNT Digital Library
The FNAL Injector Upgrade Status (open access)

The FNAL Injector Upgrade Status

The new FNAL H{sup -} injector upgrade is currently being tested before installation in the Spring 2012 shutdown of the accelerator complex. This line consists of an H{sup -} source, low energy beam transport (LEBT), 200 MHz RFQ and medium energy beam transport (MEBT). Beam measurements have been performed to validate the design before installation. The results of the beam measurements are presented in this paper.
Date: May 14, 2012
Creator: Tan, C. Y.; Bollinger, D. S.; Duel, K. L.; Karns, P. R.; Lackey, J. R.; Pellico, W. A et al.
Object Type: Article
System: The UNT Digital Library
GLOVEBOX GLOVE CHARACTERIZATION SUMMARY (open access)

GLOVEBOX GLOVE CHARACTERIZATION SUMMARY

A task was undertaken to determine primarily the permeation behavior of various glove compounds from four manufacturers. As part of the basic characterization task, the opportunity to obtain additional mechanical and thermal properties presented itself. Consequently, a total of fifteen gloves were characterized for permeation, Thermogravimetric Analysis, Puncture Resistance, Tensile Properties and Dynamic Mechanical Analysis. Detailed reports were written for each characterization technique used. This report contains the summary of the results.
Date: May 14, 2012
Creator: Korinko, P.
Object Type: Report
System: The UNT Digital Library
HFC Concrete: A Low-Energy, Carbon-Dioxide-­Negative Solution for reducing Industrial Greenhouse Gas Emissions (open access)

HFC Concrete: A Low-Energy, Carbon-Dioxide-­Negative Solution for reducing Industrial Greenhouse Gas Emissions

Solidia/CCSM received funding for further research and development of its Low Temperature Solidification Process (LTS), which is used to create hydrate-free concrete (HFC). LTS/HFC is a technology/materials platform that offers wide applicability in the built infrastructure. Most importantly, it provides a means of making concrete without Portland cement. Cement and concrete production is a major consumer of energy and source of industrial greenhouse gas (GHG) emissions. The primary goal of this project was to develop and commercialize a novel material, HFC, which by replacing traditional concrete and cement, reduces both energy use and GHG emissions in the built infrastructure. Traditional concrete uses Portland Cement (PC) as a binder. PC production involves calcination of limestone at {approx}1450 C, which releases significant amounts of CO{sub 2} gas to the atmosphere and consumes a large amount of energy due to the high temperature required. In contrast, HFC is a carbonate-based hydrate-free concrete (HFC) that consumes CO{sub 2} gas in its production. HFC is made by reaction of silicate minerals with CO{sub 2} at temperatures below 100 C, more than an order-of-magnitude below the temperature required to make PC. Because of this significant difference in temperature, it is estimated that we will be able …
Date: May 14, 2012
Creator: McCandlish, Larry & Riman, Richard
Object Type: Report
System: The UNT Digital Library
High Power UV LED Industrial Curing Systems (open access)

High Power UV LED Industrial Curing Systems

UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using …
Date: May 14, 2012
Creator: Karlicek, Robert, F., Jr & Sargent, Robert
Object Type: Report
System: The UNT Digital Library
How Measures Are Brought to the House Floor: A Brief Introduction (open access)

How Measures Are Brought to the House Floor: A Brief Introduction

This report presents a brief description of the five methods used to bring proposed legislation to the House floor for consideration. These methods allow for consideration as a privileged matter, under the limited privilege of a special calendar or day, under suspension of the rules, under the terms of a special rule, or by unanimous consent.
Date: May 14, 2012
Creator: Davis, Christopher M.
Object Type: Report
System: The UNT Digital Library
Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels (open access)

Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels

A fast vertical 1.08-m long kicker (notcher) located in the Fermilab Booster Long-05 straight section is currently used to remove 3 out of 84 circulating bunches after injection to generate an abort gap. With the maximum magnetic field of 72.5 Gauss, it removes only 87% of the 3-bunch intensity at 400 MeV, with 75% loss on pole tips of the focusing Booster magnets, 11% on the Long-06 collimators, and 1% in the rest of the ring. We propose to improve the notching efficiency and reduce beam loss in the Booster by using three horizontal kickers in the Long-12 section. STRUCT calculations show that using horizontal notchers, one can remove up to 96% of the 3-bunch intensity at 400-700 MeV, directing 95% of it to a new beam dump at the Long-13 section. This fully decouples notching and collimation. The beam dump absorbs most of the impinging proton energy in its jaws. The latter are encapsulated into an appropriate radiation shielding that reduces impact on the machine components, personnel and environment to the tolerable levels. MARS simulations show that corresponding prompt and residual radiation levels can be reduced ten times compared to the current ones.
Date: May 14, 2012
Creator: Rakhno, I. L.; Drozhdin, A. I.; Mokhov, N. V.; Sidorov, V. I. & Tropin, I. S.
Object Type: Article
System: The UNT Digital Library
Measurement of the Cosmic Ray e+ plus e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope (open access)

Measurement of the Cosmic Ray e+ plus e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m{sup 2}sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply-falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E{sup -3.0} and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.
Date: May 14, 2012
Creator: Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. et al.
Object Type: Article
System: The UNT Digital Library
Medicare: Trends in Beneficiaries Served and Hospital Resources Used in Implantable Medical Device Procedures (open access)

Medicare: Trends in Beneficiaries Served and Hospital Resources Used in Implantable Medical Device Procedures

Correspondence issued by the Government Accountability Office with an abstract that begins "Overall, orthopedic IMD admission rates were substantially higher in 2009 compared with 2003, while admission rate patterns among cardiac IMDs were mixed. Admission rates rose for each of the orthopedic IMDs in our study, with knee replacement rates growing 6.7 percent per year. The picture for inpatient cardiac IMD procedures was more mixed; admission rates for dual-chamber pacemakers decreased steadily while rates for AICDs and drug-eluting stents increased through 2006 and generally declined thereafter, in part reflecting a shift of surgeries to the outpatient setting. While the proportion of both orthopedic and cardiac IMD beneficiaries in poor or very poor health grew throughout our period of study, this trend was far more evident for cardiac IMD beneficiaries after 2007."
Date: May 14, 2012
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Multi-Physics Analysis of the Fermilab Booster RF Cavity (open access)

Multi-Physics Analysis of the Fermilab Booster RF Cavity

After about 40 years of operation the RF accelerating cavities in Fermilab Booster need an upgrade to improve their reliability and to increase the repetition rate in order to support a future experimental program. An increase in the repetition rate from 7 to 15 Hz entails increasing the power dissipation in the RF cavities, their ferrite loaded tuners, and HOM dampers. The increased duty factor requires careful modelling for the RF heating effects in the cavity. A multi-physic analysis investigating both the RF and thermal properties of Booster cavity under various operating conditions is presented in this paper.
Date: May 14, 2012
Creator: Awida, M.; Reid, J.; Yakovlev, V.; Lebedev, V.; Khabiboulline, T. & Champion, M.
Object Type: Article
System: The UNT Digital Library
NATO's Chicago Summit (open access)

NATO's Chicago Summit

NATO's 2012 summit of alliance heads of state and government is scheduled to take place in Chicago on May 20-21. U.S. and NATO officials have outlined what they expect to be the Summit's three main agenda items: Defining the next phase of formal transition in Afghanistan and shaping a longer term NATO commitment to the country after the planned end of combat operations by the end of 2014; Securing commitments to maintain and develop the military capabilities necessary to meet NATO's defense and security goals, including through a new "Smart Defense" initiative; and Enhancing NATO's partnerships with non-NATO member states.
Date: May 14, 2012
Creator: Belkin, Paul
Object Type: Report
System: The UNT Digital Library
Neutron Activation Diagnostics at the National Ignition Facility (open access)

Neutron Activation Diagnostics at the National Ignition Facility

None
Date: May 14, 2012
Creator: Bleuel, D L; Yeamans, C B; Bernstein, L A; Bionta, R M; Caggiano, J A; Casey, D T et al.
Object Type: Article
System: The UNT Digital Library
The Presidential Nominating Process and the National Party Conventions, 2012: Frequently Asked Questions (open access)

The Presidential Nominating Process and the National Party Conventions, 2012: Frequently Asked Questions

This report provides answers to frequently asked questions about the presidential nominating process, including how the delegates to the national conventions are chosen, the differences between a caucus and a primary, national party rules changes for 2012, and the national conventions themselves.
Date: May 14, 2012
Creator: Coleman, Kevin J.
Object Type: Report
System: The UNT Digital Library
Proliferation of Precision Strike: Issues for Congress (open access)

Proliferation of Precision Strike: Issues for Congress

The United States took the early lead in the development of precision strike and has enjoyed a monopoly on these systems for over 20 years. However, many experts agree that the U.S. advantage is eroding as these systems spread. Many experts believe the proliferation of precision strike has already begun and will continue to accelerate as more and more countries continue to develop and purchase precision strike weaponry. The proliferation of precision strike creates potential issues for Congress. These issues include whether the Department of Defense (DOD) is properly taking adversary precision strike weapons into account in its own plans and programs, and whether Congress should approve, reject, or modify proposed DOD programs for responding to those weapons.
Date: May 14, 2012
Creator: Huiss, Randy
Object Type: Report
System: The UNT Digital Library
REVISED GUIDELINES FOR USING CELLULOSE DEGRADATION PRODUCT-IMPACTED KD VALUES FOR PERFORMANCE ASSESSMENTS AND COMPOSITE ANALYSES (open access)

REVISED GUIDELINES FOR USING CELLULOSE DEGRADATION PRODUCT-IMPACTED KD VALUES FOR PERFORMANCE ASSESSMENTS AND COMPOSITE ANALYSES

Cellulosic materials include wood, paper, rags, and cardboard products. These materials are co-disposed with radiological waste at the Savannah River Site's (SRS) E-Area Low-Level Waste Facility (ELLWF). Cellulosic materials readily degrade in the environment to form cellulose degradation products (CDP) that will partition to the sediment or remain mobile in the groundwater. Savannah River National Lab (SRNL) has conducted studies to estimate the impact of CDP on radionuclide sorption to SRS sediments (Kd values). It was found that CDP impact on radionuclide sorption varies with radionuclide and CDP concentration. Furthermore, it was found that the amount of carbon (C) in the system could increase or decrease Kd values with respect to the base case of when no CDP was added. Throughout the expected pH range of the ELLWF, a low concentration of CDP in the system would increase Kd values (because C would sorb to the sediment and provide more exchange sites for radionuclides to sorb), whereas greater concentrations of CDP ({ge}20 mg/L C) would decrease Kd values (because C would remain in solution and complex the radionuclide and not permit the radionuclide to sorb to the sediment). A review of >230 dissolved organic carbon (DOC) groundwater concentrations in the …
Date: May 14, 2012
Creator: Kaplan, D.
Object Type: Report
System: The UNT Digital Library
Singularities of Generalized Parton Distributions (open access)

Singularities of Generalized Parton Distributions

The basic ideas of the theory of Generalized Parton Distributions (GPDs) are reviewed. Recent developments in the study of singularities of GPDs are discussed.
Date: May 14, 2012
Creator: Radyushkin, Anatoly
Object Type: Article
System: The UNT Digital Library