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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
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
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
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
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
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
Civil Pleading Requirements After Bell Atlantic Corporation v. Twombly and Ashcroft v. Iqbal (open access)

Civil Pleading Requirements After Bell Atlantic Corporation v. Twombly and Ashcroft v. Iqbal

This report discusses the U.S. Supreme Court 2007 and 2009 decisions, Bell Atlantic Corporation v. Twombly and Ashcroft v. Iqbal, governing whether a civil complaint filed in federal court will survive a motion to dismiss for failure to state a claim.
Date: July 1, 2010
Creator: Barbour, Emily C.
Object Type: Report
System: The UNT Digital Library
Assess the key physics that underpins high-hydro coupling-efficiency in NDCX-II experiments and high-gain heavy ion direct drive target designs using proven hydro codes like HYDRA (open access)

Assess the key physics that underpins high-hydro coupling-efficiency in NDCX-II experiments and high-gain heavy ion direct drive target designs using proven hydro codes like HYDRA

The simulations provided in this milestone have solidified the theoretical underpinning of direct drive targets and also the ability to design experiments on NDCX II that will enhance our understanding of ion-beam hydrodynamic coupling, and thus be relevant to IFE. For the case of the IFE targets, we have studied hydro and implosion efficiency using HYDRA in ID, a starting point towards the goal of polar direct drive in geometry compatible with liquid wall chambers. Recent analysis of direct drive fusion energy targets using heavy ion beams has found high coupling efficiency of ion beam energy into implosion energy. However, to obtain optimal coupling, the ion energy must increase during the pulse in order to penetrate the outflowing ablated material, and deposit the energy close enough to the fuel so that the fuel achieves sufficient implosion velocity. We have computationally explored ID (radial) time dependent models of ion driven direct drive capsule implosions using the Arbitrary Lagrangian-Eulerian (ALE) code HYDRA, to help validate the theoretical analysis done so far, particularly exploring the effects of varying the ion energy and ion current over the course of the pulse. On NDCX II, experiments have been proposed to explore issues of ion penetration …
Date: July 1, 2010
Creator: Barnard, J. J.; Hay, M. J.; Logan, B. G.; Ng, S. F.; Perkins, L. J.; Veitzer, S. et al.
Object Type: Report
System: The UNT Digital Library
Access to Special Nuclear Material at the Idaho National Laboratory (open access)

Access to Special Nuclear Material at the Idaho National Laboratory

Access to special nuclear material (SNM) such as enriched uranium or plutonium is critical to the experimental validation of measurement techniques for nuclear nonproliferation applications. It is especially important that realistic quantities be available for measurements in the field. Security and safety requirements have made such access nearly impossible at many U.S. facilities. The Idaho National Laboratory (INL) has been able to provide kilogram quantities of SNM for in situ measurements ranging from testing of equipment in laboratory facilities, to outdoor measurements simulating real conditions, to transfer of the SNM to the customer’s facility and back for measurements in the field. The INL will be working to make SNM more widely accessible for measurements by nuclear nonproliferation projects, including those with international researchers.
Date: July 1, 2010
Creator: Bean, R.; Barrett, J.; Gerts, D. & Brush, B.
Object Type: Article
System: The UNT Digital Library
Exploring Crystal Plasticity Via Far-Field 3DXRD (open access)

Exploring Crystal Plasticity Via Far-Field 3DXRD

None
Date: July 1, 2010
Creator: Bernier, J. V.; Barton, N. R.; Brandes, M. C.; Lienert, U.; Miller, M. P. & Mills, M. J.
Object Type: Article
System: The UNT Digital Library
ChIP-seq Identification of Weakly Conserved Heart Enhancers (open access)

ChIP-seq Identification of Weakly Conserved Heart Enhancers

Accurate control of tissue-specific gene expression plays a pivotal role in heart development, but few cardiac transcriptional enhancers have thus far been identified. Extreme non-coding sequence conservation successfully predicts enhancers active in many tissues, but fails to identify substantial numbers of heart enhancers. Here we used ChIP-seq with the enhancer-associated protein p300 from mouse embryonic day 11.5 heart tissue to identify over three thousand candidate heart enhancers genome-wide. Compared to other tissues studied at this time-point, most candidate heart enhancers are less deeply conserved in vertebrate evolution. Nevertheless, the testing of 130 candidate regions in a transgenic mouse assay revealed that most of them reproducibly function as enhancers active in the heart, irrespective of their degree of evolutionary constraint. These results provide evidence for a large population of poorly conserved heart enhancers and suggest that the evolutionary constraint of embryonic enhancers can vary depending on tissue type.
Date: July 1, 2010
Creator: Blow, Matthew J.; McCulley, David J.; Li, Zirong; Zhang, Tao; Akiyama, Jennifer A.; Holt, Amy et al.
Object Type: Article
System: The UNT Digital Library
Initial inclusion of thermodynamic considerations in Kayenta. (open access)

Initial inclusion of thermodynamic considerations in Kayenta.

A persistent challenge in simulating damage of natural geological materials, as well as rock-like engineered materials, is the development of efficient and accurate constitutive models. The common feature for these brittle and quasi-brittle materials are the presence of flaws such as porosity and network of microcracks. The desired models need to be able to predict the material responses over a wide range of porosities and strain rate. Kayenta (formerly called the Sandia GeoModel) is a unified general-purpose constitutive model that strikes a balance between first-principles micromechanics and phenomenological or semi-empirical modeling strategies. However, despite its sophistication and ability to reduce to several classical plasticity theories, Kayenta is incapable of modeling deformation of ductile materials in which deformation is dominated by dislocation generation and movement which can lead to significant heating. This stems from Kayenta's roots as a geological model, where heating due to inelastic deformation is often neglected or presumed to be incorporated implicitly through the elastic moduli. The sophistication of Kayenta and its large set of extensive features, however, make Kayenta an attractive candidate model to which thermal effects can be added. This report outlines the initial work in doing just that, extending the capabilities of Kayenta to include …
Date: July 1, 2010
Creator: Brannon, Rebecca Moss (University of Utah, Salt Lake City, UT); Bishop, Joseph E.; Fuller, Timothy J. (University of Utah, Salt Lake City, UT) & Strack, Otto Eric
Object Type: Report
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 118, No. 127, Ed. 1 Thursday, July 1, 2010 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 118, No. 127, Ed. 1 Thursday, July 1, 2010

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: July 1, 2010
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Canadian Record (Canadian, Tex.), Vol. 120, No. 26, Ed. 1 Thursday, July 1, 2010 (open access)

The Canadian Record (Canadian, Tex.), Vol. 120, No. 26, Ed. 1 Thursday, July 1, 2010

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: July 1, 2010
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
Improving Higgs Sensitivity at CDF by Introducing New Muon Triggers (open access)

Improving Higgs Sensitivity at CDF by Introducing New Muon Triggers

A search for Standard Model Higgs boson production in the H {yields} WW {yields} {ell}{nu}jj channel using 5.7 fb{sup -1} of CDF II data is presented. The search is performed using a matrix element technique in which event probability densities for the signal and background hypotheses are calculated and used to create a powerful disciminator (called the event probability discriminant, EPD). The EPD distributions for signal and background are fit to the data using a binned likelihood approach to search for the Higgs boson signal. To improve the limits on the H production cross section, a new muon category, CMP, is added. No evidence for a Higgs boson signal is observed, and 95% confidence level upper limits on the H cross section times the branching ratio of the Higgs boson to decay to two W of {sigma}(p{bar p} {yields} H) x BR(H {yields} WW)/SM &lt; 7.7 to 62.1 for Higgs boson masses of between m{sub H} = 150 GeV/c{sup 2} and m{sub H} = 200 GeV/c{sup 2} are found. The expected (median) limit estimated in pseudo-experiments is {sigma}(p{bar p} {yields} H) x BR(H {yields} WW)/SM &lt; 12.5 to 41.0 at 95% C.L. The inclusion of the phi gap trigger lead …
Date: July 1, 2010
Creator: Buchmann, Marco-Andrea
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 112, No. 148, Ed. 1 Thursday, July 1, 2010 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 148, Ed. 1 Thursday, July 1, 2010

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 1, 2010
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Draft genome sequence of Therminicola potens strain JR (open access)

Draft genome sequence of Therminicola potens strain JR

'Thermincola potens' strain JR is one of the first Gram-positive dissimilatory metal-reducing bacteria (DMRB) for which there is a complete genome sequence. Consistent with the physiology of this organism, preliminary annotation revealed an abundance of multiheme c-type cytochromes that are putatively associated with the periplasm and cell surface in a Gram-positive bacterium. Here we report the complete genome sequence of strain JR.
Date: July 1, 2010
Creator: Byrne-Bailey, K. G.; Wrighton, K. C.; Melnyk, R. A.; Agbo, P.; Hazen, T. C. & Coates, J. D.
Object Type: Article
System: The UNT Digital Library
Hydrogen Permeability of Incoloy 800H, Inconel 617, and Haynes 230 Alloys (open access)

Hydrogen Permeability of Incoloy 800H, Inconel 617, and Haynes 230 Alloys

A potential issue in the design of the NGNP reactor and high-temperature components is the permeation of fission generated tritium and hydrogen product from downstream hydrogen generation through high-temperature components. Such permeation can result in the loss of fission-generated tritium to the environment and the potential contamination of the helium coolant by permeation of product hydrogen into the coolant system. The issue will be addressed in the engineering design phase, and requires knowledge of permeation characteristics of the candidate alloys. Of three potential candidates for high-temperature components of the NGNP reactor design, the hydrogen permeability has been documented well only for Incoloy 800H, but at relatively high partial pressures of hydrogen. Hydrogen permeability data have been published for Inconel 617, but only in two literature reports and for partial pressures of hydrogen greater than one atmosphere, far higher than anticipated in the NGNP reactor. The hydrogen permeability of Haynes 230 has not been published. To support engineering design of the NGNP reactor components, the hydrogen permeability of Inconel 617 and Haynes 230 were determined using a measurement system designed and fabricated at the Idaho National Laboratory. The performance of the system was validated using Incoloy 800H as reference material, for …
Date: July 1, 2010
Creator: Calderoni, Pattrick
Object Type: Report
System: The UNT Digital Library