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First Direct Bound on the Total Width of the Top Quark in p anti-p Collisions at s88(1/2) = 1.96-TeV (open access)

First Direct Bound on the Total Width of the Top Quark in p anti-p Collisions at s88(1/2) = 1.96-TeV

None
Date: August 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Search for Doubly Charged Higgs Bosons with Lepton-Flavor-Violating Decays involving Tau Leptons (open access)

Search for Doubly Charged Higgs Bosons with Lepton-Flavor-Violating Decays involving Tau Leptons

None
Date: August 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Search for Supersymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV Using the Trilepton Signature of Chargino-Neutralino Production (open access)

Search for Supersymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV Using the Trilepton Signature of Chargino-Neutralino Production

None
Date: August 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
ZZ ---> l+ l- v anti-v production in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

ZZ ---> l+ l- v anti-v production in p anti-p collisions at s**(1/2) = 1.96-TeV

None
Date: August 1, 2008
Creator: Abazov, V. M.; /Dubna, JINR; Abbott, B.; U., /Oklahoma; Abolins, M.; U., /Michigan State et al.
Object Type: Article
System: The UNT Digital Library
Measurement of differential Z / gamma* + jet + X cross sections in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of differential Z / gamma* + jet + X cross sections in p anti-p collisions at s**(1/2) = 1.96-TeV

We present new measurements of differential cross sections for Z/{gamma}* ({yields} {mu}{mu})+jet+X production in a 1 fb{sup -1} data sample collected with the D0 detector in p{bar p} collisions at {radical}s = 1.96 TeV. Results include the first measurements differential in the Z/{gamma}* transverse momentum and rapidity, as well as new measurements differential in the leading jet transverse momentum and rapidity. Next-to-leading order perturbative QCD predictions are compared to the measurements, and reasonable agreement is observed, except in the region of low Z/{gamma}* transverse momentum. Predictions from two event generators based on matrix elements and parton showers, and one pure parton shower event generator are also compared to the measurements. These show significant overall normalization differences to the data and have varied success in describing the shape of the distributions.
Date: August 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of sigma(p anti-p ---> Z + X) Br(Z ---> tau+tau-) at s**(1/2) = 1.96-TeV (open access)

Measurement of sigma(p anti-p ---> Z + X) Br(Z ---> tau+tau-) at s**(1/2) = 1.96-TeV

None
Date: August 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for pair production of second generation scalar leptoquarks (open access)

Search for pair production of second generation scalar leptoquarks

We report on a search for the pair production of second generation scalar leptoquarks (LQ) in p{bar p} collisions at the center of mass energy {radical}s = 1.96TeV using a data set corresponding to an integrated luminosity of 1.0 fb{sup -1} collected with the D0 experiment at the Fermilab Tevatron Collider. Topologies arising from the LQ{ovr LQ} {yields} {mu}q{nu}q and LQ{ovr LQ} {yields} {mu}q{mu}q decay modes are investigated. No excess of data over the standard model prediction is observed and upper limits on the leptoquark pair production cross section are derived at the 95% C.L. as a function of the leptoquark mass and the branching fraction {beta} for the decay LQ {yields} {mu}q. These are interpreted as lower limits on the leptoquark mass as a function of {beta}. For {beta} = 1 (0.5), scalar second generation leptoquarks with masses up to 316GeV (270GeV) are excluded.
Date: August 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
A Search for the standard model Higgs boson in the missing energy and acoplanar b-jet topology at s**(1/2) = 1.96-TeV (open access)

A Search for the standard model Higgs boson in the missing energy and acoplanar b-jet topology at s**(1/2) = 1.96-TeV

None
Date: August 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Top Quark Mass Measurements at the Tevatron (open access)

Top Quark Mass Measurements at the Tevatron

Top quark mass measurements from the Tevatron using up to 2.0 fb{sup -1} of data are presented. Prospects for combined Tevatron measurements by the end of Run II are discussed.
Date: August 1, 2008
Creator: Adelman, Jahred
Object Type: Article
System: The UNT Digital Library
HINS Linac front end focusing system R&D (open access)

HINS Linac front end focusing system R&D

This report summarizes current status of an R&D program to develop a focusing system for the front end of a superconducting RF linac. Superconducting solenoids will be used as focusing lenses in the low energy accelerating sections of the front end. The development of focusing lenses for the first accelerating section is in the production stage, and lens certification activities are in preparation at FNAL. The report contains information about the focusing lens design and performance, including solenoid, dipole corrector, and power leads, and about cryogenic system design and performance. It also describes the lens magnetic axis position measurement technique and discusses scope of an acceptance/certification process.
Date: August 1, 2008
Creator: Apollinari, G.; Carcagno, R. H.; Dimarco, J.; Huang, Y.; Kashikhin, V. V.; Orris, D. F. et al.
Object Type: Article
System: The UNT Digital Library
Development of 325 MHz single spoke resonators at Fermilab (open access)

Development of 325 MHz single spoke resonators at Fermilab

The High Intensity Neutrino Source (HINS) project represents the current effort at Fermilab to produce an 8-GeV proton linac based on 400 independently phased superconducting cavities. Eighteen ?=0.21 single spoke resonators, operating at 325 MHz, comprise the first stage of the linac cold section. In this paper we present the current status of the production and testing of the first two prototype cavities. This includes descriptions of the fabrication, frequency tuning, chemical polishing, high pressure rinse, and high-gradient cold tests.
Date: August 1, 2008
Creator: Apollinari, G.; Gonin, I.V.; Khabiboulline, T.N.; Lanfranco, G.; Mukherjee, A.; Ozelis, J. et al.
Object Type: Article
System: The UNT Digital Library
The Hutto Business Update (Hutto, Tex.), Vol. 4, No. 2, Ed. 1 Friday, August 1, 2008 (open access)

The Hutto Business Update (Hutto, Tex.), Vol. 4, No. 2, Ed. 1 Friday, August 1, 2008

Newsletter focusing on information for and about the business community in Hutto, Texas, along with advertising.
Date: August 1, 2008
Creator: Arnett, Mahlon E., II
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Measurement of Ratios of Branching Fractions and CP-Violating Asymmetries of B+/- --> D*K +/- decays (open access)

Measurement of Ratios of Branching Fractions and CP-Violating Asymmetries of B+/- --> D*K +/- decays

The authors report a study of B{sup {+-}} {yields} D*K{sup {+-}} decays with D* decaying to D{pi}{sup 0} or D{gamma}, using 383 x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. The D meson decays under study include a non-CP mode (K{sup {+-}}{pi}{sup {-+}}), CP-even modes (K{sup {+-}}K{sup {-+}}, {pi}{sup {+-}}{pi}{sup {-+}}) and CP-odd modes (K{sub S}{sup 0}{pi}{sup 0}, K{sub S}{sup 0}{phi}, K{sub S}{sup 0}{omega}). They measure ratios (R*{sub CP{+-}}) of branching fractions of decays to CP eigenmode states and to flavor-specific states as well as CP asymmetries A*{sub CP{+-}} = -0.11 {+-} 0.09 {+-} 0.01, R*{sub CP+} = 1.31 {+-} 0.13 {+-} 0.04, and A*{sub CP-} = 0.06 {+-} 0.10 {+-} 0.02, R*{sub CP-} = 1.10 {+-} 0.12 {+-} 0.04, where the first error is statistical and the second error is systematic. Translating the results into an alternative parameterization, widely used for related measurements, they obtain x*{sub +} = 0.11 {+-} 0.06 {+-} 0.02 and x*{sub -} = 0.00 {+-} 0.06 {+-} 0.01. No significant CP-violating charge asymmetry is found in either the flavor-specific mode D {yields} K{sup {+-}}{pi}{sup {-+}} or in B{sup {+-}} {yields} D*{pi}{sup {+-}} decays.
Date: August 1, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays (open access)

Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays

The authors present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. This update includes all data taken at the {Upsilon}(4S) resonance by the BABAR experiment at the asymmetric PEP-II B-meson factory at SLAC, corresponding to 467 {+-} 5 million B{bar B} pairs. They find S{sub {pi}{pi}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{pi}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sub {pi}}} = -0.107 {+-} 0.016{sub -0.004},{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where the first error is statistical and the second is systematic. They observe CP violation with a significance of 6.7{sigma} in B{sup 0} {yields} {pi}{sup -} and 6.1{sigma} in B{sup 0} {yields} K{sup +}{pi}{sup -}. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relation between all B {yields} {pi}{pi} rates and asymmetries.
Date: August 1, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Search for B+ --> mu+ nu_mu With Inclusive Reconstruction at BaBar (open access)

Search for B+ --> mu+ nu_mu With Inclusive Reconstruction at BaBar

We search for the purely leptonic decay B{sup {+-}} {yields} {mu}{sup {+-}}{nu}{sub {mu}} in the full BABAR dataset, having an integrated luminosity of approximately 426 fb{sup -1}. We adopt a fully inclusive approach, where the signal candidate is identified by the highest momentum lepton in the event and the companion B is inclusively reconstructed without trying to identify its decay products. We set a preliminary upper limit on the branching fraction of {Beta}(B{sup {+-}} {yields} {mu}{sup {+-}}{nu}{sub {mu}}) < 1.3 x 10{sup -6} at the 90% confidence level, using a Bayesian approach.
Date: August 1, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Searches for B Meson Decays to Phiphi, Phirho, Phif0(980), and f0(980)f0(980) Final States (open access)

Searches for B Meson Decays to Phiphi, Phirho, Phif0(980), and f0(980)f0(980) Final States

We present the results of searches for B decays to charmless final states involving {phi}, f{sub 0}(980), and charged or neutral {rho} mesons. The data sample corresponds to 384 x 10{sup 6} B{bar B} pairs collected with the BABAR detector operating at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. We find no significant signals and determine the following 90% confidence level upper limits on the branching fractions, including systematic uncertainties: {Beta}(B{sup 0} {yields} {phi}{phi}) < 2.0 x 10{sup -7}, {Beta}(B{sup +} {yields} {phi}{rho}{sup +}) < 30 x 10{sup -7}, {Beta}(B{sup 0} {yields} {phi}{rho}{sup 0}) < 3.3 x 10{sup -7}, {Beta}[B{sup 0} {yields} {phi}f{sub 0}(980)] x {Beta}[f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}] < 3.8 x 10{sup -7}, and {Beta}[B{sup 0} {yields} f{sub 0}(980)f{sub 0}(980)] x {Beta}[f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}] x {Beta}[f{sub 0}(980) {yields} K{sup +}K{sup -}] < 2.3 x 10{sup -7}.
Date: August 1, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Washington International Renewable Energy Conference 2008 Pledges: Methodology and Assumptions Summary (open access)

Washington International Renewable Energy Conference 2008 Pledges: Methodology and Assumptions Summary

The 2008 Washington International Renewable Energy Conference (WIREC) was held in Washington, D.C., from March 4-6, 2008, and involved nearly 9,000 people from 125 countries. The event brought together worldwide leaders in renewable energy (RE) from governments, international organizations, nongovernmental organizations, and the private sector to discuss the role that renewables can play in alleviating poverty, growing economies, and passing on a healthy planet to future generations. The conference concluded with more than 140 governments, international organizations, and private-sector representatives pledging to advance the uptake of renewable energy. The U.S. government authorized the National Renewable Energy Laboratory (NREL) to estimate the carbon dioxide (CO2) savings that would result from the pledges made at the 2008 conference. This report describes the methodology and assumptions used by NREL in quantifying the potential CO2 reductions derived from those pledges.
Date: August 1, 2008
Creator: Babiuch, B.; Bilello, D. E.; Cowlin, S. C.; Mann, M. & Wise, A.
Object Type: Report
System: The UNT Digital Library
Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 6, Ed. 1 Friday, August 1, 2008 (open access)

Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 6, Ed. 1 Friday, August 1, 2008

Monthly periodical from Oklahoma City, Oklahoma published by and for members of the Oklahoma State Firefighters Association that includes news and information along with advertising.
Date: August 1, 2008
Creator: Bain, Chris
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History
Pursuing Energy Efficiency as a Hedge against Carbon Regulatory Risks: Current Resource Planning Practices in the West (open access)

Pursuing Energy Efficiency as a Hedge against Carbon Regulatory Risks: Current Resource Planning Practices in the West

Uncertainty surrounding the nature and timing of future carbon regulations poses a fundamental and far-reaching financial risk for electric utilities and their ratepayers. Long-term resource planning provides a potential framework within which utilities can assess carbon regulatory risk and evaluate options for mitigating exposure to this risk through investments in energy efficiency and other low-carbon resources. In this paper, we examine current resource planning practices related to managing carbon regulatory risk, based on a comparative analysis of the most-recent long-term resource plans filed by fifteen major utilities in the Western U.S. First, we compare the assumptions and methods used by utilities to assess carbon regulatory risk and to evaluate energy efficiency as a risk mitigation option. Although most utilities have made important strides in beginning to address carbon regulatory risk within their resource plan, we also identify a number of opportunities for improvement and offer recommendations for resource planners and state regulators to consider. We also summarize the composition and carbon intensity of the preferred resource portfolios selected by the fifteen Western utilities, highlighting the contribution of energy efficiency and its impact on the carbon intensity of utilities' proposed resource strategies. Energy efficiency and renewables are the dominant low-carbon resources …
Date: August 1, 2008
Creator: Barbose, Galen; Wiser, Ryan; Phadke, Amol & Goldman, Charles
Object Type: Article
System: The UNT Digital Library
Ion Beam Heated Target Simulations for Warm Dense Matter Physics and Inertial Fusion Energy (open access)

Ion Beam Heated Target Simulations for Warm Dense Matter Physics and Inertial Fusion Energy

Hydrodynamic simulations have been carried out using the multi-physics radiation hydrodynamics code HYDRA and the simplified one-dimensional hydrodynamics code DISH. We simulate possible targets for a near-term experiment at LBNL (the Neutralized Drift Compression Experiment, NDCX) and possible later experiments on a proposed facility (NDCX-II) for studies of warm dense matter and inertial fusion energy related beam-target coupling. Simulations of various target materials (including solids and foams) are presented. Experimental configurations include single pulse planar metallic solid and foam foils. Concepts for double-pulsed and ramped-energy pulses on cryogenic targets and foams have been simulated for exploring direct drive beam target coupling, and concepts and simulations for collapsing cylindrical and spherical bubbles to enhance temperature and pressure for warm dense matter studies are described.
Date: August 1, 2008
Creator: Barnard, J. J.; Armijo, J.; Bailey, D. S.; Friedman, A.; Bieniosek, F. M.; Henestroza, E. et al.
Object Type: Article
System: The UNT Digital Library
Surface Plasmon Enhanced Phosphorescent Organic Light Emitting Diodes (open access)

Surface Plasmon Enhanced Phosphorescent Organic Light Emitting Diodes

The objective of the proposed work was to develop the fundamental understanding and practical techniques for enhancement of Phosphorescent Organic Light Emitting Diodes (PhOLEDs) performance by utilizing radiative decay control technology. Briefly, the main technical goal is the acceleration of radiative recombination rate in organometallic triplet emitters by using the interaction with surface plasmon resonances in noble metal nanostructures. Increased photonic output will enable one to eliminate constraints imposed on PhOLED efficiency by triplet-triplet annihilation, triplet-polaron annihilation, and saturation of chromophores with long radiative decay times. Surface plasmon enhanced (SPE) PhOLEDs will operate more efficiently at high injection current densities and will be less prone to degradation mechanisms. Additionally, introduction of metal nanostructures into PhOLEDs may improve their performance due to the improvement of the charge transport through organic layers via multiple possible mechanisms ('electrical bridging' effects, doping-like phenomena, etc.). SPE PhOLED technology is particularly beneficial for solution-fabricated electrophosphorescent devices. Small transition moment of triplet emitters allows achieving a significant enhancement of the emission rate while keeping undesirable quenching processes introduced by the metal nanostructures at a reasonably low level. Plasmonic structures can be introduced easily into solution-fabricated PhOLEDs by blending and spin coating techniques and can be used for …
Date: August 1, 2008
Creator: Bazan, Guillermo & Mikhailovsky, Alexander
Object Type: Report
System: The UNT Digital Library
Race, Genetics and Medicine: New Information, Enduring Questions (open access)

Race, Genetics and Medicine: New Information, Enduring Questions

Final Report on Conference held on April 9, 2005 and its Sequelae The Conference, “Race, Genetics and Medicine: New Information, Enduring Questions,” was held on Saturday, April 9, 2005 in the Science Center, Lecture Hall D at Harvard University, Cambridge, MA. Approximately 150 people attended. The audience was composed mainly of college and graduate school science students and postdoctoral fellows, some science and medical school faculty, science teachers at various levels, journalists and interested members of the public. The keynote speaker and the panelists reflected different academic disciplines (genetics, medicine, anthropology, sociology) and a CEO of a biotechnology company with background in medicine and law. They also presented different perspectives on the utility of race concepts in medicine and even on the use of the word “race.” While the talks often involved descriptions of genetic approaches that were not simple to explain, the speakers did an effective job of getting across the gist of studies that have been carried out on these issues. Although no consensus was reached, the conference gave the audience the opportunity to understand the issues and to have the tools to follow the debates in the future. Our strongest feedback was from attendees who had heard …
Date: August 1, 2008
Creator: Beckwith, Jonathan R.
Object Type: Article
System: The UNT Digital Library
One-Loop Calculations with BlackHat (open access)

One-Loop Calculations with BlackHat

We describe BlackHat, an automated C++ program for calculating one-loop amplitudes, and the techniques used in its construction. These include the unitarity method and on-shell recursion. The other ingredients are compact analytic formulae for tree amplitudes for four-dimensional helicity states. The program computes amplitudes numerically, using analytic formula only for the tree amplitudes, the starting point for the recursion, and the loop integrals. We make use of recently developed on-shell methods for evaluating coefficients of loop integrals, in particular a discrete Fourier projection as a means of improving numerical stability. We illustrate the good numerical stability of this approach by computing six-, seven- and eight-gluon amplitudes in QCD and comparing against known analytic results.
Date: August 1, 2008
Creator: Berger, C.F.; Bern, Z.; Dixon, L.J.; Cordero, F.Febres; Forde, D.; Ita, H. et al.
Object Type: Article
System: The UNT Digital Library
The Anti-B ---> D* l anti-nu form factor at zero recoil from three-flavor lattice QCD: A Model independent determination of |V(cb)| (open access)

The Anti-B ---> D* l anti-nu form factor at zero recoil from three-flavor lattice QCD: A Model independent determination of |V(cb)|

None
Date: August 1, 2008
Creator: Bernard, C.; DeTar, C.; Di Pierro, M.; El-Khadra, A. X.; Evans, R. T.; Freeland, E. D. et al.
Object Type: Article
System: The UNT Digital Library