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Search for Hadronic Decays of W and Z Bosons in Photon Events in p anti-p Collisions at s**(1/2) = 1.96-GeV (open access)

Search for Hadronic Decays of W and Z Bosons in Photon Events in p anti-p Collisions at s**(1/2) = 1.96-GeV

None
Date: March 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF (open access)

Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF

We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector which correspond to an integrated luminosity of approximately 1 fb{sup -1}. We select events consistent with a signature of a single lepton (e{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method and a neural network filter technique. The observed number of events and the dijet mass distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching ratio ranging from 3.9 to 1.3 pb for Higgs boson masses from 110 to 150 GeV/c{sup 2}, respectively.
Date: March 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
Evidence for production of single top quarks (open access)

Evidence for production of single top quarks

We present first evidence for the production of single top quarks in the D0 detector at the Fermilab Tevatron p{bar p} collider. The standard model predicts that the electroweak interaction can produce a top quark together with an antibottom quark or light quark, without the antiparticle top quark partner that is always produced from strong coupling processes. Top quarks were first observed in pair production in 1995, and since then, single top quark production has been searched for in ever larger datasets. In this analysis, we select events from a 0.9 fb{sup -1} dataset that have an electron or muon and missing transverse energy from the decay of a W boson from the top quark decay, and two, three, or four jets, with one or two of the jets identified as originating from a b hadron decay. The selected events are mostly backgrounds such as W+jets and t{bar t} events, which we separate from the expected signals using three multivariate analysis techniques: boosted decision trees, Bayesian neural networks, and matrix element calculations. A binned likelihood fit of the signal cross section plus background to the data from the combination of the results from the three analysis methods gives a cross …
Date: March 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
First study of the radiation-amplitude zero in W gamma production and limits on anomalous WW gamma couplings at s**(1/2) = 1.96- TeV (open access)

First study of the radiation-amplitude zero in W gamma production and limits on anomalous WW gamma couplings at s**(1/2) = 1.96- TeV

None
Date: March 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 the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section (open access)

Measurement of the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section

None
Date: March 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 the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV

We measure the t{bar t} production cross section in p{bar p} collisions at {radical}s = 1.96 TeV in the lepton+jets channel. Two complementary methods discriminate between signal and background, b-tagging and a kinematic likelihood discriminant. Based on 0.9 fb{sup -1} of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure {sigma}{sub t{bar t}} = 7.62 {+-} 0.85 pb, assuming the current world average m{sub t} = 172.6 GeV. We compare our cross section measurement with theory predictions to determine a value for the top quark mass of 170 {+-} 7 GeV.
Date: March 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 h(f) ---> gamma gamma with the D0 detector at s**(1/2) = 1.96-TeV (open access)

Search for h(f) ---> gamma gamma with the D0 detector at s**(1/2) = 1.96-TeV

None
Date: March 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 large extra dimensions in the mono-photon final state at s**(1/2) = 1.96-TeV (open access)

Search for large extra dimensions in the mono-photon final state at s**(1/2) = 1.96-TeV

The authors report on a search for large extra dimensions in a data sample of approximately 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV. They investigate Kaluza-Klein graviton production with a photon and missing transverse energy in the final state. At the 95% C.L. they set limits on the fundamental mass scale M{sub D} from 884 GeV to 778 GeV for 2 to 8 extra dimensions.
Date: March 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 scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV

None
Date: March 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 W-prime Boson Resonances Decaying to a Top Quark and a Bottom Quark (open access)

Search for W-prime Boson Resonances Decaying to a Top Quark and a Bottom Quark

We search for the production of a heavy W{prime} gauge boson that decays to third generation quarks in 0.9 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the D0 detector at the Fermilab Tevatron collider. We find no significant excess in the final-state invariant mass distribution and set upper limits on the production cross section times branching fraction. For a left-handed W{prime} boson with SM couplings, we set a lower mass limit of 731 GeV. For right-handed W{prime} bosons, we set lower mass limits of 739 GeV if the W{prime} boson decays to both leptons and quarks and 768 GeV if the W{prime} boson decays only to quarks. We also set limits on the coupling of the W{prime} boson to fermions as a function of its mass.
Date: March 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 the K+ --> pi+ nu nu branching ratio (open access)

Measurement of the K+ --> pi+ nu nu branching ratio

Experiment E949 at Brookhaven National Laboratory studied the rare decay K{sup +}-->pi{sup +} nu{ovr {nu}} and other processes with an exposure of 1.77 x 10{sup 12} k{sup +}'s. The data were analyzed using a blind analysis technique yielding one candidate event with an estimated background of 0.30 {+-} 0.03 events. Combining this result with the observation of two candidate events by the predecessor experiment E787 gave the branching ratio B(K{sup +}-->pi{sup +} nu{ovr {nu}}) = (1.47{sub -0.89}{sup +1.30}) x 10{sup -10}, consistent with the standard model prediction of (0.74 {+-} 0.20) x 10{sup -10}. This is a more detailed report of results previously published [V.V. Anisimovsky et al., Phys. Rev. Lett. 93, 031801 (2004)].
Date: March 1, 2008
Creator: Adler, S.; Anisimovsky, V. V.; Aoki, M.; Ardebili, M.; Artamonov, A. V.; Atiya, M. et al.
Object Type: Article
System: The UNT Digital Library
First Observation of Coherent pi0 Production in Neutrino Nucleus Interactions with E(nu) < 2 GeV (open access)

First Observation of Coherent pi0 Production in Neutrino Nucleus Interactions with E(nu) < 2 GeV

The MiniBooNE experiment at Fermilab has amassed the largest sample to date of {pi}{sup 0}s produced in neutral current (NC) neutrino-nucleus interactions at low energy. This paper reports a measurement of the momentum distribution of {pi}{sup 0}s produced in mineral oil (CH{sub 2}) and the first observation of coherent {pi}{sup 0} production below 2 GeV. In the forward direction, the yield of events observed above the expectation for resonant production is attributed primarily to coherent production off carbon, but may also include a small contribution from diffractive production on hydrogen. Integrated over the MiniBooNE neutrino flux, the sum of the NC coherent and diffractive modes is found to be (19.5 {+-} 1.1 (stat) {+-} 2.5 (sys))% of all exclusive NC {pi}{sup 0} production at MiniBooNE. These measurements are of immediate utility because they quantify an important background to MiniBooNE's search for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations.
Date: March 1, 2008
Creator: Aguilar-Arevalo, A. A.; Anderson, C. E.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J. et al.
Object Type: Article
System: The UNT Digital Library
Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation (open access)

Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation

The authors show how models of neutrino masses and mixings can be differentiated on the basis of their predictions for {theta}{sub 13} and lepton flavor violation in radiative charged lepton decays and {mu} - e conversion. They illustrate the lepton flavor violation results for five predictive SO(10) SUSY GUT models and point out the relative importance of their heavy right-handed neutrino mass spectra and {theta}{sub 13} predictions.
Date: March 1, 2008
Creator: Albright, Carl H.
Object Type: Article
System: The UNT Digital Library
Results of the 2007 B100 Quality Survey (open access)

Results of the 2007 B100 Quality Survey

In a 2007 analysis of samples from 52% of U.S. biodiesel (B100) producers, 90% met ASTM and other specifications for critical engine performance properties and for elements that harm emission controls.
Date: March 1, 2008
Creator: Alleman, T. L. & McCormick, R. L.
Object Type: Report
System: The UNT Digital Library
Mechanical considerations and design skills. (open access)

Mechanical considerations and design skills.

The purpose of the report is to provide experienced-based insights into design processes that will benefit designers beginning their employment at Sandia National Laboratories or those assuming new design responsibilities. The main purpose of this document is to provide engineers with the practical aspects of system design. The material discussed here may not be new to some readers, but some of it was to me. Transforming an idea to a design to solve a problem is a skill, and skills are similar to history lessons. We gain these skills from experience, and many of us have not been fortunate enough to grow in an environment that provided the skills that we now need. I was fortunate to grow up on a farm where we had to learn how to maintain and operate several different kinds of engines and machines. If you are like me, my formal experience is partially based upon the two universities from which I graduated, where few practical applications of the technologies were taught. What was taught was mainly theoretical, and few instructors had practical experience to offer the students. I understand this, as students have their hands full just to learn the theoretical. The practical part …
Date: March 1, 2008
Creator: Alvis, Robert L.
Object Type: Report
System: The UNT Digital Library
Nuclear Engineering Enrollments and Degrees Survey, 2007 Data (open access)

Nuclear Engineering Enrollments and Degrees Survey, 2007 Data

The survey includes degrees granted between September 1, 2006, and August 1, 2007, and fall 2007 enrollments. Thirty-one academic programs reported having nuclear engineering programs during 2007, and data was obtained for all thirty-one.
Date: March 1, 2008
Creator: Analysis and Evaluation, Science Education Programs
Object Type: Report
System: The UNT Digital Library
The Hutto Business Update (Hutto, Tex.), Vol. 4, No. 1, Ed. 1 Saturday, March 1, 2008 (open access)

The Hutto Business Update (Hutto, Tex.), Vol. 4, No. 1, Ed. 1 Saturday, March 1, 2008

Newsletter focusing on information for and about the business community in Hutto, Texas, along with advertising.
Date: March 1, 2008
Creator: Arnett, Mahlon E., II
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Shillapoo Wildlife Area 2007 Follow-up HEP Report. (open access)

Shillapoo Wildlife Area 2007 Follow-up HEP Report.

In April and May 2007 the Regional HEP Team (RHT) conducted a follow-up HEP analysis on the Egger (612 acres) and Herzog (210 acres) parcels located at the north end of the Shillapoo Wildlife Area. The Egger and Herzog parcels have been managed with Bonneville Power Administration funds since acquired in 1998 and 2001 respectively. Slightly more than 936 habitat units (936.47) or 1.14 HUs per acre was generated as an outcome of the 2007 follow-up HEP surveys. Results included 1.65 black-capped chickadee HUs, 280.57 great blue heron HUs, 581.45 Canada goose HUs, 40 mallard HUs, and 32.80 mink HUs. Introduction A follow-up Habitat Evaluation Procedures (HEP) (USFWS 1980) analysis was conducted by the Columbia Basin Fish and Wildlife Authority's (CBFWA) Regional HEP Team (RHT) during April and May 2007 to document changes in habitat quality and to determine the number of habitat units (HUs) to credit Bonneville Power Administration (BPA) for providing operation and maintenance (O&amp;M) funds since WDFW acquired the parcels. The 2007 follow-up HEP evaluation was limited to Shillapoo Wildlife Area (SWA) parcels purchased with Bonneville Power Administration funds. D. Budd (pers. comm.) reported WDFW purchased the 612 acre Egger Farms parcel on November 2, 1998 for …
Date: March 1, 2008
Creator: Ashley, Paul R.
Object Type: Report
System: The UNT Digital Library
Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 2, Ed. 1 Saturday, March 1, 2008 (open access)

Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 2, Ed. 1 Saturday, March 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: March 1, 2008
Creator: Bain, Chris
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History
Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 1: Main Report (open access)

Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 1: Main Report

A phenomena identification and ranking table (PIRT) process was conducted for the Next Generation Nuclear Plant (NGNP) design. This design (in the conceptual stage) is a modular high-temperature gas-cooled reactor (HTGR) that generates both electricity and process heat for hydrogen production. Expert panels identified safety-relevant phenomena, ranked their importance, and assessed the knowledge levels in the areas of accidents and thermal fluids, fission-product transport and dose, high-temperature materials, graphite, and process heat for hydrogen production. This main report summarizes and documents the process and scope of the reviews, noting the major activities and conclusions. The identified phenomena, analyses, rationales, and associated ratings of the phenomena, plus a summary of each panel's findings, are presented. Individual panel reports for these areas are provided as attached volumes to this main report and provide considerably more detail about each panel's deliberations as well as a more complete listing of the phenomena that were evaluated.
Date: March 1, 2008
Creator: Ball, Sydney J
Object Type: Report
System: The UNT Digital Library
Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 2: Accident and Thermal Fluids Analysis PIRTs (open access)

Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 2: Accident and Thermal Fluids Analysis PIRTs

An accident, thermal fluids, and reactor physics phenomena identification and ranking process was conducted by a panel of experts on the next generation nuclear plant (NGNP) design (consideration given to both pebble-bed and prismatic gas-cooled reactor configurations). Safety-relevant phenomena, importance, and knowledge base were assessed for the following event classes: (1) normal operation (including some reactor physics aspects), (2) general loss of forced circulation (G-LOFC), (3) pressurized loss-of-forced circulation (P-LOFC), (4) depressurized loss-of-forced circulation (D-LOFC), (5) air ingress (following D-LOFC), (6) reactivity transients - including anticipated transients without scram (ATWS), (7) processes coupled via intermediate heat exchanger (IHX) (IHX failure with molten salt), and (8) steam/water ingress. The panel's judgment of the importance ranking of a given phenomenon (or process) was based on the effect it had on one or more figures of merit or evaluation criteria. These included public and worker dose, fuel failure, and primary (and other safety) system integrity. The major phenomena of concern that were identified and categorized as high importance combined with medium to low knowledge follow: (1) core coolant bypass flows (normal operation), (2) power/flux profiles (normal operation), (3) outlet plenum flows (normal operation), (4) reactivity-temperature feedback coefficients for high-plutonium-content cores (normal operation and …
Date: March 1, 2008
Creator: Ball, Sydney J; Corradini, M.; Fisher, Stephen Eugene; Gauntt, R.; Geffraye, G.; Gehin, Jess C et al.
Object Type: Report
System: The UNT Digital Library
NAWIG News: The Quarterly Newsletter of the Native American Wind Interest Group, Spring 2008 (open access)

NAWIG News: The Quarterly Newsletter of the Native American Wind Interest Group, Spring 2008

The United States is home to more than 700 American Indian tribes and Native Alaska villages and corporations located on 96 million acres. Many of these tribes and villages have excellent wind resources that could be commercially developed to meet their electricity needs or for electricity export. The Wind Powering America program engages Native Americans in wind energy development, and as part of that effort, the NAWIG newsletter informs readers of events in the Native American/wind energy community. This issue features an interview with Steven J. Morello, director of DOE's newly formed Office of Indian Energy Policy and Programs, and a feature on the newly installed Vestas V-47 turbine at Turtle Mountain Community College.
Date: March 1, 2008
Creator: Baranowski, R.
Object Type: Report
System: The UNT Digital Library
Framework for Proliferation Resistance and Physical Protection for Nonproliferation Impact Assessments. (open access)

Framework for Proliferation Resistance and Physical Protection for Nonproliferation Impact Assessments.

This report describes a framework for proliferation resistance and physical protection evaluation for the fuel cycle systems envisioned in the expansion of nuclear power for electricity generation. The methodology is based on an approach developed as part of the Generation IV technical evaluation framework and on a qualitative evaluation approach to policy factors similar to those that were introduced in previous Nonproliferation Impact Assessments performed by DOE.
Date: March 1, 2008
Creator: Bari, R.
Object Type: Report
System: The UNT Digital Library
BAE/Orion Hybrid Electric Buses at New York City Transit: A Generational Comparison (Revised) (open access)

BAE/Orion Hybrid Electric Buses at New York City Transit: A Generational Comparison (Revised)

Paper describes the evaluation of hybrid-electric transit buses purchased by New York City Transit (NYCT) in an order group of 200 (Gen II) and compares their performance to those of similar hybrid-electric transit buses purchased by NYCT in an order group of 125 (Gen I).
Date: March 1, 2008
Creator: Barnitt, R.
Object Type: Report
System: The UNT Digital Library