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Qcd physics: measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96 tev (open access)

Qcd physics: measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96 tev

We report a measurement of the rate of prompt diphoton production in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 207 pb{sup -1} collected with the upgraded Collider Detector at Fermilab (CDF II). The background from non-prompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.
Date: June 13, 2005
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Measurement of the Moments of the Hadronic Invariant Mass Distribution in Semileptonic Beta Decays (open access)

Measurement of the Moments of the Hadronic Invariant Mass Distribution in Semileptonic Beta Decays

Using 180 pb{sup -1} of data collected with the CDF II detector at the Tevatron, we measure the first two moments of the hadronic invariant mass-squared distribution in charmed semileptonic B decays. From these we determine the non-perturbative Heavy Quark Effective Theory parameters {Lambda} and {lambda}{sub 1} used to relate the B meson semileptonic branching ratio to the CKM matrix element |V{sub cb}|.
Date: March 13, 2005
Creator: Acosta, D. & TITLE=Measuremen, The CDF Collaboration
Object Type: Report
System: The UNT Digital Library
Surface Passivation of Germanium Nanowires (open access)

Surface Passivation of Germanium Nanowires

The surface of single crystal, cold-wall CVD-grown germanium nanowires was studied by synchrotron radiation photoemission spectroscopy (SR-PES) and also by conventional XPS. The as-grown germanium nanowires seem to be hydrogen terminated. Exposure to laboratory atmosphere leads to germanium oxide growth with oxidation states of Ge{sup 1+}, Ge{sup 2+}, Ge{sup 3+}, while exposure to UV light leads to a predominance of the Ge{sup 4+} oxidation state. Most of the surface oxide could be removed readily by aqueous HF treatment which putatively leaves the nanowire surface hydrogen terminated with limited stability in air. Alternatively, chlorine termination could be achieved by aq. HCl treatment of the native oxide-coated nanowires. Chlorine termination was found to be relatively more stable than the HF-last hydrogen termination.
Date: May 13, 2005
Creator: Adhikari, Hemant; Sun, Shiyu; Pianetta, Piero; Chidsey, Chirstopher E.D.; McIntyre, Paul C. & /SLAC, SSRL
Object Type: Report
System: The UNT Digital Library
Morocco-U.S. Free Trade Agreement (open access)

Morocco-U.S. Free Trade Agreement

The United States and Morocco reached agreement on March 2, 2004, to create a free trade agreement (FTA). The FTA is intended to strengthen bilateral ties, boost trade and investment flows, and bolster Morocco’s position as a moderate Arab state. More than 95% of bilateral trade in consumer and industrial products will become duty-free upon entry into force of the agreement. The Senate approved implementing legislation (S. 2677) on July 2, 2004, by a vote of 85-13 and the House approved identical legislation (H.R. 4842) on July 22, 2004, by a vote of 323-99. The next day, the Senate passed House approved H.R. 4842 without amendment by unanimous consent.
Date: April 13, 2005
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
Mapping cis-Regulatory Domains in the Human Genome UsingMulti-Species Conservation of Synteny (open access)

Mapping cis-Regulatory Domains in the Human Genome UsingMulti-Species Conservation of Synteny

Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A total of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a genes regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide a genome wide data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.
Date: June 13, 2005
Creator: Ahituv, Nadav; Prabhakar, Shyam; Poulin, Francis; Rubin, EdwardM. & Couronne, Olivier
Object Type: Article
System: The UNT Digital Library
The Need for a Neutron Source at the Rare Isotope Accelerator (open access)

The Need for a Neutron Source at the Rare Isotope Accelerator

An intense neutron source facility with radiochemical processing capability is necessary at the Rare Isotope Accelerator to fully realize its potential benefit to stockpile stewardship and astrophysics. While many of the important physics missions of RIA can be addressed with radioactive ion beams, direct neutron cross-section measurements of interest to stockpile stewardship and astrophysics cannot because one cannot make a neutron target. Thus, one must collect a sufficient amount of the appropriate short-lived isotope, quickly chemically process the material into a target, and promptly radiate the sample with an intense ''beam'' of neutrons. The unprecedented production rates expected at RIA enables many of these direct neutron cross-section measurements, but only if the proper infrastructure is in place. This document not only describes the major piece of this required infrastructure, a neutron source facility with radiochemical processing capabilities, but also the motivation for measuring such direct neutron cross-sections.
Date: May 13, 2005
Creator: Ahle, L. E.; Rusnak, B.; Roberts, K. E.; Roeben, M. D.; Hausmann, M.; Reifarth, R. et al.
Object Type: Report
System: The UNT Digital Library
Smart Fuel Cell Operated Residential Micro-Grid Community (open access)

Smart Fuel Cell Operated Residential Micro-Grid Community

To build on the work of year one by expanding the smart control algorithm developed to a micro-grid of ten houses; to perform a cost analysis; to evaluate alternate energy sources; to study system reliability; to develop the energy management algorithm, and to perform micro-grid software and hardware simulations.
Date: April 13, 2005
Creator: Alam, Mohammad S.
Object Type: Report
System: The UNT Digital Library
MODELING THE TRANSPORT AND CHEMICAL EVOLUTION OF ONSHORE AND OFFSHORE EMISSIONS AND THEIR IMPACT ON LOCAL AND REGIONAL AIR QUALITY USING A VARIABLE-GRID-RESOLUTION AIR QUALITY MODEL (open access)

MODELING THE TRANSPORT AND CHEMICAL EVOLUTION OF ONSHORE AND OFFSHORE EMISSIONS AND THEIR IMPACT ON LOCAL AND REGIONAL AIR QUALITY USING A VARIABLE-GRID-RESOLUTION AIR QUALITY MODEL

This second annual report summarizes the research performed from 17 April 2004 through 16 April 2005. Major portions of the research in several of the project's current eight tasks have been completed. We have successfully developed the meteorological inputs using the best possible modeling configurations, resulting in improved representation of atmospheric processes. The development of the variable-grid-resolution emissions model, SMOKE-VGR, is also completed. The development of the MAQSIP-VGR has been completed and a test run was performed to ensure the functionality of this air quality model. Thus, the project is on schedule as planned. During the upcoming reporting period, we expect to perform the first MAQSIP-VGR simulations over the Houston-Galveston region to study the roles of the meteorology, offshore emissions, and chemistry-transport interactions that determine the temporal and spatial evolution of ozone and its precursors.
Date: May 13, 2005
Creator: Alapaty, Kiran
Object Type: Report
System: The UNT Digital Library
Colleges and Universities Attended by Representatives of the 109th Congress (open access)

Colleges and Universities Attended by Representatives of the 109th Congress

This report identifies the colleges and universities attended by representatives, delegates and the Resident Commissioner in the 109th Congress grouped by state.
Date: September 13, 2005
Creator: Amer, Mildred L.
Object Type: Report
System: The UNT Digital Library
Colleges and Universities Attended by Senators of the 109th Congress (open access)

Colleges and Universities Attended by Senators of the 109th Congress

This report identifies the colleges and universities attended by Senators serving in the 109th Congress. Where available in published sources, the degrees earned are also listed.
Date: September 13, 2005
Creator: Amer, Mildred L.
Object Type: Report
System: The UNT Digital Library
U.S.-EU Cooperation Against Terrorism (open access)

U.S.-EU Cooperation Against Terrorism

None
Date: April 13, 2005
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
A Study of $e^+e^-\to p\bar{p}$ Using Initial StateRadiation with BaBar (open access)

A Study of $e^+e^-\to p\bar{p}$ Using Initial StateRadiation with BaBar

The e{sup +}e{sup -} {yields} p{bar p} cross-section is determined over a range of p{bar p} masses, from threshold to 4.5 GeV/c{sup 2}, by studying the e{sup +}e{sup -} {yields} p{bar p}{gamma} process. The data set corresponds to an integrated luminosity of 232 fb{sup -1}, collected with the BABAR detector at the PEP-II storage ring, at an e{sup +}e{sup -} center-of-mass energy of 10.6 GeV. The mass dependence of the ratio of electric and magnetic form factors, |G{sub E}/G{sub M}|, is measured for p{bar p} masses below 3 GeV/c{sup 2}; its value is found to be significantly larger than 1 for masses up to 2.2 GeV/c{sup 2}. We also measure J/{psi} {yields} p{bar p} and {psi}(2S) {yields} p{bar p} branching fractions and set an upper limit on Y(4260) {yields} p{bar p} production and decay.
Date: December 13, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model (open access)

Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model

In this paper, we use a coupled climate and carbon cycle model to investigate the global climate and carbon cycle changes out to year 2300 that would occur if CO2 emissions from all the currently estimated fossil fuel resources were released to the atmosphere. By year 2300, the global climate warms by about 8 K and atmospheric CO2 reaches 1423 ppmv. In our simulation, the prescribed cumulative emission since pre-industrial period is about 5400 Gt-C by the end of 23rd century. At year 2300, nearly 45 % of cumulative emissions remain in the atmosphere. In our simulations both soils and living biomass are net carbon sinks throughout the simulation. Despite having relatively low climate sensitivity and strong carbon uptake by the land biosphere, our model projections suggest severe long-term consequences for global climate if all the fossil-fuel carbon is ultimately released to the atmosphere.
Date: June 13, 2005
Creator: Bala, G.; Caldeira, K.; Mirin, A.; Wickett, M. & Delire, C.
Object Type: Article
System: The UNT Digital Library
Energy Policy: Comprehensive Energy Legislation (H.R. 6) in the 109th Congress (open access)

Energy Policy: Comprehensive Energy Legislation (H.R. 6) in the 109th Congress

The House passed H.R. 6, the Energy Policy Act of 2005, on April 21, 2005 (249-183). The legislation includes a “safe harbor” provision to protect methyl tertiary-butyl ether (MTBE) refiners from product liability suits, which was retained after a close vote on an amendment to drop the language (213-219). In the 108th Congress, there was opposition to this provision in the Senate. It is unclear how its inclusion may affect Senate passage of an energy bill in the 109th Congress. House Republicans have indicated that a compromise will be sought to satisfy the other body. Language in the House-passed bill would also authorize opening of the Arctic National Wildlife Refuge (ANWR) to exploration and development. An amendment to delete the ANWR provisions from H.R. 6 was defeated (200-231).
Date: May 13, 2005
Creator: Bamberger, Robert L. & Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
Laser Safety Inspection Criteria (open access)

Laser Safety Inspection Criteria

A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms It is common for audit findings from one inspector or inspection to the next to vary even when reviewing the same material. How often has one heard a comment, ''well this area has been inspected several times over the years and no one ever said this or that was a problem before''. A great number of audit items, and therefore findings, are subjective because they are based on the experience and interest of the auditor to particular items on the checklist. Beam block usage, to one set of eyes might be completely adequate, while to another, inadequate. In order to provide consistency, the Laser Safety Office of the National Ignition Facility …
Date: June 13, 2005
Creator: Barat, K.
Object Type: Article
System: The UNT Digital Library
High-Significance Sunyaev-Zel'dovich Measurement: Abell 1914 Seen With the Arcminute Microkelvin Imager (open access)

High-Significance Sunyaev-Zel'dovich Measurement: Abell 1914 Seen With the Arcminute Microkelvin Imager

We report the first detection of a Sunyaev-Zel'dovich (S-Z) decrement with the Arcminute Microkelvin Imager (AMI). We have made commissioning observations towards the cluster A1914 and have measured an integrated flux density of -8.61 mJy in a uv-tapered map with noise level 0.19 mJy/beam. We find that the spectrum of the decrement, measured in the six channels between 13.5-18 GHz, is consistent with that expected for a S-Z effect. The sensitivity of the telescope is consistent with the figures used in our simulations of cluster surveys with AMI.
Date: September 13, 2005
Creator: Barker, Robert; Biddulph, Phillip; Bly, Dennis; Boysen, Roger; Brown, Anthony; Clementson, Christopher et al.
Object Type: Report
System: The UNT Digital Library
Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter (open access)

Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter

One approach for heating a target to ''Warm Dense Matter'' conditions (similar, for example, to the interiors of giant planets or certain stages in Inertial Confinement Fusion targets), is to use intense ion beams as the heating source (see refs.[6] and [7] and references therein for motivation and accelerator concepts). By consideration of ion beam phase space constraints, both at the injector, and at the final focus, and consideration of simple equations of state and relations for ion stopping, approximate conditions at a target foil may be calculated. Thus target temperature and pressure may be calculated as a function of ion mass, ion energy, pulse duration, velocity tilt, and other accelerator parameters. We connect some of these basic parameters to help search the extensive parameter space (including ion mass, ion energy, total charge in beam pulse, beam emittance, target thickness and density).
Date: May 13, 2005
Creator: Barnard, J. J.; Briggs, R. J.; Callahan, D. A.; Davidson, R. C.; Friedman, A.; Grisham, L. et al.
Object Type: Article
System: The UNT Digital Library
Ultrafast magnetization dynamics studies using an x-ray streakcamera (open access)

Ultrafast magnetization dynamics studies using an x-ray streakcamera

The spin dynamics of ferromagnetic thin films following an excitation by ultrashort 100-fs near-infrared laser pulses has recently received much attention. Here, a new approach is described using x-ray magnetic circular dichroism to investigated emagnetization and magnetization switching processes. In contrast to magneto-optical measurements, x-ray dichroism has the advantage of determining separately the spin and orbital components of the magnetic moment. The relatively low time resolution of the synchrotron x-ray probe pulses (80 ps FWHM) is overcome by employing an ultrafast x-ray streak camera with a time resolution of <1 ps. A description of the experimental setup including the x-ray/IR laser pulse synchronization and the streak camera is given.
Date: July 13, 2005
Creator: Bartelt, A. F.; Comin, A.; Feng, J.; Nasiatka, J.; Padmore, H. A.; Scholl, A. et al.
Object Type: Article
System: The UNT Digital Library
Contrasting Supersymmetry and Universal Extra Dimensions at the CLIC Multi-TeV e+e- Collider (open access)

Contrasting Supersymmetry and Universal Extra Dimensions at the CLIC Multi-TeV e+e- Collider

Universal extra dimensions and supersymmetry have rather similar experimental signatures at hadron colliders. The proper interpretation of an LHC discovery in either case may therefore require further data from a lepton collider. In this paper we identify methods for discriminating between the two scenarios at the linear collider. We study the processes of Kaluza-Klein muon pair production in universal extra dimensions in parallel to smuon pair production in supersymmetry, accounting for the effects of detector resolution, beam-beam interactions and accelerator induced backgrounds. We find that the angular distributions of the final state muons, the energy spectrum of the radiative return photon and the total cross-section measurement are powerful discriminators between the two models. Accurate determination of the particle masses can be obtained both by a study of the momentum spectrum of the final state leptons and by a scan of the particle pair production thresholds. We also calculate the production rates of various Kaluza-Klein particles and discuss the associated signatures.
Date: July 13, 2005
Creator: Battaglia, Marco; Datta, AseshKrishna; De Roeck, Albert; Kong, Kyoungchul & Matchev, Konstantin T.
Object Type: Article
System: The UNT Digital Library
Mad Cow Disease: Agricultural Issues for Congress (open access)

Mad Cow Disease: Agricultural Issues for Congress

In December 2003 a Holstein dairy cow in Washington State tested positive for BSE (bovine spongiform encephalopathy, or mad cow disease), the first case discovered in the The United States and the second native casein North America. (Canada confirmed a third and then the fourth case in early January 2005.)
Date: January 13, 2005
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
Bovine Spongiform Encephalopathy (BSE, or "Mad Cow Disease"): Current and Proposed Safeguards (open access)

Bovine Spongiform Encephalopathy (BSE, or "Mad Cow Disease"): Current and Proposed Safeguards

This report presents an overview of bovine spongiform encephalopathy (BSE, or “mad cow disease”) in the United States. Shortly after the first case of BSE was announced, U.S. Department of Agriculture (USDA) and other officials announced measures to improve existing safeguards against the introduction and spread of BSE. This report discusses trade restrictions, the live-stock “feed ban”, as well as the BSE surveillance and testing in cattle.
Date: October 13, 2005
Creator: Becker, Geoffrey S. & Lister, Sarah A.
Object Type: Report
System: The UNT Digital Library
Nuclear Nonproliferation Issues (open access)

Nuclear Nonproliferation Issues

This report includes information regarding nuclear proliferation issues. Aspects of this report discuss international nonproliferation structures, U.S. policy, and nuclear proliferation in specific regions.
Date: January 13, 2005
Creator: Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
2nd American Conference on Neutron Scattering (open access)

2nd American Conference on Neutron Scattering

Final report on 2nd American Conference on Neutron Scattering.
Date: April 13, 2005
Creator: Belanger, David P.
Object Type: Report
System: The UNT Digital Library
DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS (open access)

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from …
Date: July 13, 2005
Creator: Bernot, P.
Object Type: Report
System: The UNT Digital Library