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Diffractive W and Z Production at the Fermilab Tevatron (open access)

Diffractive W and Z Production at the Fermilab Tevatron

We report on a measurement of the fraction of events with a W or Z boson produced diffractively in {bar p}p collisions at {radical}s = 1.96 TeV, using data from 0.6 fb{sup -1} of integrated luminosity collected with the CDF II detector equipped with a Roman-pot spectrometer that detects the {bar p} from {bar p} + p {yields} {bar p}+[X+W/Z]. We find that (0.97 {+-} 0.11)% of Ws and (0.85 {+-} 0.22)% of Zs are produced diffractively in a region of (anti)proton fractional momentum loss {zeta} of 0.03 < {zeta} < 0.10 and 4-momentum transferred squared t of -1 < t < 0 (GeV/c){sup 2}. We also report on searches for W and Z production in double Pomeron exchange, p+{bar p} {yields} p+[X+W/z]+{bar p}, and on exclusive Z production, {bar p}p {yields} {bar p}+Z+p. No signal is seen above background for these processes, and comparisons are made with expectations.
Date: July 1, 2010
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Cantabria Inst. of; Amerio, S.; /INFN, Padua et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the $t\bar{t}$ Production Cross Section with an in situ Calibration of $b$-jet Identification Efficiency (open access)

Measurement of the $t\bar{t}$ Production Cross Section with an in situ Calibration of $b$-jet Identification Efficiency

A measurement of the top-quark pair-production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using data corresponding to an integrated luminosity of 1.12 fb{sup -1} collected with the Collider Detector at Fermilab is presented. Decays of top-quark pairs into the final states e{nu} + jets and {mu}{nu} + jets are selected, and the cross section and the b-jet identification efficiency are determined using a new measurement technique which requires that the measured cross sections with exactly one and multiple identified b-quarks from the top-quark decays agree. Assuming a top-quark mass of 175 GeV/c{sup 2}, a cross section of 8.5 {+-} 0.6(stat.) {+-} 0.7(syst.) pb is measured.
Date: July 1, 2010
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Cantabria Inst. of; Amerio, S.; /INFN, Padua et al.
Object Type: Article
System: The UNT Digital Library
Search for sneutrino production in $e\mu$ final states in 5.3 fb$^{-1}$ of $p\bar{p}$ collisions at $\sqrt(s) =1.96$ TeV (open access)

Search for sneutrino production in $e\mu$ final states in 5.3 fb$^{-1}$ of $p\bar{p}$ collisions at $\sqrt(s) =1.96$ TeV

We report the results of a search for R parity violating (RPV) interactions leading to the production of supersymmetric sneutrinos decaying into e{mu} final states using 5.3 fb{sup -1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider. Having observed no evidence for production of e{mu} resonances, we set direct bounds on the RPV couplings {lambda}{prime}{sub 311} and {lambda}{sub 312} as a function of sneutrino mass.
Date: July 1, 2010
Creator: Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; U., /Oklahoma; Abolins, Maris A.; U., /Michigan State et al.
Object Type: Article
System: The UNT Digital Library
Evidence for an anomalous like-sign dimuon charge asymmetry (open access)

Evidence for an anomalous like-sign dimuon charge asymmetry

None
Date: July 1, 2010
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Abolins, Maris A.; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd et al.
Object Type: Article
System: The UNT Digital Library
INDEPENDENT VERIFICATION SURVEY REPORT OPERABLE UNIT-1 LANDFILL TRENCHES, MIAMISBURG CLOSURE PROJECT (open access)

INDEPENDENT VERIFICATION SURVEY REPORT OPERABLE UNIT-1 LANDFILL TRENCHES, MIAMISBURG CLOSURE PROJECT

INDEPENDENT VERIFICATION SURVEY REPORT FOR THE OPERABLE UNIT-1 LANDFILL TRENCHES, MIAMISBURG CLOSURE PROJECT, MIAMISBURG, OHIO DCN: 0468-SR-03-0
Date: July 21, 2010
Creator: Adams, W.C.
Object Type: Report
System: The UNT Digital Library
A Search for Lorentz Invariance and CPT Violation with the MINOS Far Detector (open access)

A Search for Lorentz Invariance and CPT Violation with the MINOS Far Detector

We searched for a sidereal modulation in the MINOS far detector neutrino rate. Such a signal would be a consequence of Lorentz and CPT violation as described by the Standard-Model Extension framework. It also would be the first detection of a perturbative effect to conventional neutrino mass oscillations. We found no evidence for this sidereal signature and the upper limits placed on the magnitudes of the Lorentz and CPT violating coefficients describing the theory are an improvement by factors of 20-510 over the current best limits found using the MINOS near detector.
Date: July 1, 2010
Creator: Adamson, P.; Auty, D. J.; Ayres, D. S.; Backhouse, C.; Barr, G.; Barrett, W. L. et al.
Object Type: Article
System: The UNT Digital Library
Structure and Electronic Properties of Cerium Orthophosphate: Theory and Experiment (open access)

Structure and Electronic Properties of Cerium Orthophosphate: Theory and Experiment

Structural and electronic properties of cerium orthophosphate (CePO{sub 4}) are calculated using density functional theory (DFT) with the local spin-density approximation (LSDA+U), with and without gradient corrections (GGA-(PBE)+U), and compared to X-ray diffraction and photoemission spectroscopy measurements. The density of states is found to change significantly as the Hubbard parameter U, which is applied to the Ce 4f states, is varied from 0 to 5 eV. The calculated structural properties are in good agreement with experiment and do not change significantly with U. Choosing U = 3 eV for LDSA provides the best agreement between the calculated density of states and the experimental photoemission spectra.
Date: July 27, 2010
Creator: Adelstein, Nicole; Mun, B. Simon; Ray, Hannah; Ross Jr, Phillip; Neaton, Jeffrey & De Jonghe, Lutgard
Object Type: Article
System: The UNT Digital Library
The climate of HD 189733b from fourteen transits and eclipses measured by Spitzer (open access)

The climate of HD 189733b from fourteen transits and eclipses measured by Spitzer

We present observations of six transits and six eclipses of the transiting planet system HD 189733 taken with the Spitzer Space Telescope IRAC camera at 8 microns, as well as a re-analysis of previously published data. We use several novel techniques in our data analysis, the most important of which is a new correction for the detector 'ramp' variation with a double-exponential function which performs better and is a better physical model for this detector variation. Our main scientific findings are: (1) an upper limit on the variability of the day-side planet flux of 2.7% (68% confidence); (2) the most precise set of transit times measured for a transiting planet, with an average accuracy of 3 seconds; (3) a lack of transit-timing variations, excluding the presence of second planets in this system above 20% of the mass of Mars in low-order mean-motion resonance at 95% confidence; (4) a confirmation of the planet's phase variation, finding the night side is 64% as bright as the day side, as well as an upper limit on the night-side variability of 17% (68% confidence); (5) a better correction for stellar variability at 8 micron causing the phase function to peak 3.5 hours before secondary …
Date: July 1, 2010
Creator: Agol, E.; /Washington U., Seattle, Astron. Dept. /Santa Barbara, KITP /UC, Santa Barbara; Cowan, Nicolas B.; /Washington U., Seattle, Astron. Dept.; Knutson, Heather A.; /UC, Berkeley, Astron. Dept. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Neutrino Neutral-Current Elastic Differential Cross Section on Mineral Oil at E sub nu ~ 1 GeV (open access)

Measurement of the Neutrino Neutral-Current Elastic Differential Cross Section on Mineral Oil at E sub nu ~ 1 GeV

We report a measurement of the flux-averaged neutral-current elastic differential cross section for neutrinos scattering on mineral oil (CH{sub 2}) as a function of four-momentum transferred squared, Q{sup 2}. It is obtained by measuring the kinematics of recoiling nucleons with kinetic energy greater than 50 MeV which are readily detected in MiniBooNE. This differential cross-section distribution is fit with fixed nucleon form factors apart from an axial mass, M{sub A}, that provides a best fit for M{sub A} = 1.39 {+-} 0.11 GeV. Using the data from the charged-current neutrino interaction sample, a ratio of neutral-current to charged-current quasi-elastic cross sections as a function of Q{sup 2} has been measured. Additionally, single protons with kinetic energies above 350 MeV can be distinguished from neutrons and multiple nucleon events. Using this marker, the strange quark contribution to the neutral-current axial vector form factor at Q{sup 2} = 0, {Delta}s, is found to be {Delta}s = 0.08{+-} 0.26.
Date: July 1, 2010
Creator: Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, B. C.; Bugel, L. et al.
Object Type: Article
System: The UNT Digital Library
MHD Simulations of Core Collapse Supernovae with Cosmos++ (open access)

MHD Simulations of Core Collapse Supernovae with Cosmos++

None
Date: July 8, 2010
Creator: Akiyama, S & Salmonson, J
Object Type: Article
System: The UNT Digital Library
Advanced Compton scattering light source R&D at LLNL (open access)

Advanced Compton scattering light source R&D at LLNL

None
Date: July 30, 2010
Creator: Albert, F.; Anderson, S. G.; Anderson, G.; Bayramian, A.; Betts, S. M.; Chu, T. S. et al.
Object Type: Article
System: The UNT Digital Library
Air Shipment of Highly Enriched Uranium Spent Nuclear Fuel from Romania (open access)

Air Shipment of Highly Enriched Uranium Spent Nuclear Fuel from Romania

Romania safely air shipped 23.7 kilograms of Russian origin highly enriched uranium (HEU) spent nuclear fuel from the VVR S research reactor at Magurele, Romania, to the Russian Federation in June 2009. This was the world’s first air shipment of spent nuclear fuel transported in a Type B(U) cask under existing international laws without special exceptions for the air transport licenses. This shipment was coordinated by the Russian Research Reactor Fuel Return Program (RRRFR), part of the U.S. Department of Energy Global Threat Reduction Initiative (GTRI), in cooperation with the Romania National Commission for Nuclear Activities Control (CNCAN), the Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), and the Russian Federation State Corporation Rosatom. The shipment was transported by truck to and from the respective commercial airports in Romania and the Russian Federation and stored at a secure nuclear facility in Russia where it will be converted into low enriched uranium. With this shipment, Romania became the 3rd country under the RRRFR program and the 14th country under the GTRI program to remove all HEU. This paper describes the work, equipment, and approvals that were required to complete this spent fuel air shipment.
Date: July 1, 2010
Creator: Allen, K. J.; Bolshinsky, I.; Biro, L. L.; Budu, M. E.; Zamfir, N. V. & Dragusin, M.
Object Type: Article
System: The UNT Digital Library
IDENTIFYING IMPURITIES IN SURPLUS NON PIT PLUTONIUM FEEDS FOR MOX OR ALTERNATIVE DISPOSITION (open access)

IDENTIFYING IMPURITIES IN SURPLUS NON PIT PLUTONIUM FEEDS FOR MOX OR ALTERNATIVE DISPOSITION

This report provides a technical basis for estimating the level of corrosion products in materials stored in DOE-STD-3013 containers based on extrapolating available chemical sample results. The primary focus is to estimate the levels of nickel, iron, and chromium impurities in plutonium-bearing materials identified for disposition in the United States Mixed Oxide fuel process.
Date: July 14, 2010
Creator: Allender, J & Moore, E
Object Type: Article
System: The UNT Digital Library
NREL GHP [Geothermal Heat Pump] Showcase: GHP Installation and Intensive in situ and Performance Monitoring at NREL's Solar Radiation and Research Laboratory; Preprint (open access)

NREL GHP [Geothermal Heat Pump] Showcase: GHP Installation and Intensive in situ and Performance Monitoring at NREL's Solar Radiation and Research Laboratory; Preprint

This document provides an overview of the geothermal heat pump (GHP) showcase at NREL and how it will help the SRRL site move forward with the goal of being a model of sustainability within the NREL campus, providing an effective demonstration of GHP systems and needed space conditioning for laboratory expansion.
Date: July 1, 2010
Creator: Anderson, E. R.
Object Type: Article
System: The UNT Digital Library
Cyber Threats to Nuclear Infrastructures (open access)

Cyber Threats to Nuclear Infrastructures

Nuclear facility personnel expend considerable efforts to ensure that their facilities can maintain continuity of operations against both natural and man-made threats. Historically, most attention has been placed on physical security. Recently however, the threat of cyber-related attacks has become a recognized and growing world-wide concern. Much attention has focused on the vulnerability of the electric grid and chemical industries to cyber attacks, in part, because of their use of Supervisory Control and Data Acquisition (SCADA) systems. Lessons learned from work in these sectors indicate that the cyber threat may extend to other critical infrastructures including sites where nuclear and radiological materials are now stored. In this context, this white paper presents a hypothetical scenario by which a determined adversary launches a cyber attack that compromises the physical protection system and results in a reduced security posture at such a site. The compromised security posture might then be malevolently exploited in a variety of ways. The authors conclude that the cyber threat should be carefully considered for all nuclear infrastructures.
Date: July 1, 2010
Creator: Anderson, Robert S.; Moskowitz, Paul; Schanfein, Mark; Bjornard, Trond & Michel, Curtis St.
Object Type: Article
System: The UNT Digital Library
Further Developments on the Geothermal System Scoping Model: Preprint (open access)

Further Developments on the Geothermal System Scoping Model: Preprint

This paper discusses further developments and refinements for the uses of the Geothermal System Scoping Model in an effort to provide a means for performing a variety of trade-off analyses of surface and subsurface parameters, sensitivity analyses, and other systems engineering studies in order to better inform R&D direction and investment for the development of geothermal power into a major contributor to the U.S. energy supply.
Date: July 1, 2010
Creator: Antkowiak, M.; Sargent, R. & Geiger, J. W.
Object Type: Article
System: The UNT Digital Library
Beyond the Death of Linear Response: 1/f Optimal Information Transport (open access)

Beyond the Death of Linear Response: 1/f Optimal Information Transport

Article discussing research on linear response and 1/f optimal information transport.
Date: July 21, 2010
Creator: Aquino, Gerardo; Bologna, Mauro; Grigolini, Paolo & West, Bruce J.
Object Type: Article
System: The UNT Digital Library
U.S.-EU Cooperation Against Terrorism (open access)

U.S.-EU Cooperation Against Terrorism

This report examines the evolution of counterterrorism cooperation between the United States and the European Union (EU), particularly since the September 11, 2001 terrorist attacks. It includes a discussion of U.S.-EU cooperation progress and ongoing challenges, as well as perspectives and issues for Congress.
Date: July 9, 2010
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
Guinea: Background and Relations with the United States (open access)

Guinea: Background and Relations with the United States

This report discusses the current political conditions in Guinea, as well as the considerable changes to Guinea's political landscape that have taken place over the past two years. The report also discusses U.S. interests and associated policy challenges in Guinea, centering around democratization, counternarcotics issues, regional stability, and socioeconomic development, among other issues.
Date: July 19, 2010
Creator: Arieff, Alexis & Cook, Nicolas
Object Type: Report
System: The UNT Digital Library
International Criminal Court Cases in Africa: Status and Policy Issues (open access)

International Criminal Court Cases in Africa: Status and Policy Issues

This report provides background on the International Criminal Court (ICC) and its investigations in Africa, with an overview of cases currently before the Court. The report also examines issues raised by the ICC's actions in Africa, including the potential deterrence of future abuses and the potential impact on African peace processes.
Date: July 14, 2010
Creator: Arieff, Alexis; Margesson, Rhoda; Browne, Marjorie Ann & Weed, Matthew C.
Object Type: Report
System: The UNT Digital Library
Ultrafast observation of shocked states in a precompressed material (open access)

Ultrafast observation of shocked states in a precompressed material

None
Date: July 8, 2010
Creator: Armstrong, M R; Crowhurst, J C; Bastea, S & Zaug, J M
Object Type: Article
System: The UNT Digital Library
Measurement of the absolute v<sub>μ</sub>-CCQE cross section at the SciBooNE experiment (open access)

Measurement of the absolute v<sub>μ</sub>-CCQE cross section at the SciBooNE experiment

This thesis presents the measurement of the charged current quasi-elastic (CCQE) neutrino-nucleon cross section at neutrino energies around 1 GeV. This measurement has two main physical motivations. On one hand, the neutrino-nucleon interactions at few GeV is a region where existing old data are sparse and with low statistics. The current measurement populates low energy regions with higher statistics and precision than previous experiments. On the other hand, the CCQE interaction is the most useful interaction in neutrino oscillation experiments. The CCQE channel is used to measure the initial and final neutrino fluxes in order to determine the neutrino fraction that disappeared. The neutrino oscillation experiments work at low neutrino energies, so precise measurement of CCQE interactions are essential for flux measurements. The main goal of this thesis is to measure the CCQE absolute neutrino cross section from the SciBooNE data. The SciBar Booster Neutrino Experiment (SciBooNE) is a neutrino and anti-neutrino scattering off experiment. The neutrino energy spectrum works at energies around 1 GeV. SciBooNE was running from June 8th 2007 to August 18th 2008. In that period, the experiment collected a total of 2.65 x 10<sup>20</sup> protons on target (POT). This thesis has used full data collection in …
Date: July 1, 2010
Creator: Aunion, Jose Luis Alcaraz
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exascale for Energy: The Role of Exascale Computing in Energy Security (open access)

Exascale for Energy: The Role of Exascale Computing in Energy Security

How will the United States satisfy energy demand in a tightening global energy marketplace while, at the same time, reducing greenhouse gas emissions? Exascale computing -- expected to be available within the next eight to ten years ? may play a crucial role in answering that question by enabling a paradigm shift from test-based to science-based design and engineering. Computational modeling of complete power generation systems and engines, based on scientific first principles, will accelerate the improvement of existing energy technologies and the development of new transformational technologies by pre-selecting the designs most likely to be successful for experimental validation, rather than relying on trial and error. The predictive understanding of complex engineered systems made possible by computational modeling will also reduce the construction and operations costs, optimize performance, and improve safety. Exascale computing will make possible fundamentally new approaches to quantifying the uncertainty of safety and performance engineering. This report discusses potential contributions of exa-scale modeling in four areas of energy production and distribution: nuclear power, combustion, the electrical grid, and renewable sources of energy, which include hydrogen fuel, bioenergy conversion, photovoltaic solar energy, and wind turbines. Examples of current research are taken from projects funded by the U.S. …
Date: July 15, 2010
Creator: Authors, Various
Object Type: Report
System: The UNT Digital Library
Detection of Hohlraum Target Position for Laser Fusion Experiments (open access)

Detection of Hohlraum Target Position for Laser Fusion Experiments

None
Date: July 6, 2010
Creator: Awwal, A. A.
Object Type: Article
System: The UNT Digital Library