Accelerated Testing Validation (open access)

Accelerated Testing Validation

The DOE Fuel Cell technical team recommended ASTs were performed on 2 different MEAs (designated P5 and HD6) from Ballard Power Systems. These MEAs were also incorporated into stacks and operated in fuel cell bus modules that were either operated in the field (three P5 buses) in Hamburg, or on an Orange county transit authority drive cycle in the laboratory (HD6 bus module). Qualitative agreement was found in the degradation mechanisms and rates observed in the AST and in the field. The HD6 based MEAs exhibited lower voltage degradation rates (due to catalyst corrosion) and slower membrane degradation rates in the field as reflected by their superior performance in the high potential hold and open-circuit potential AST tests. The quantitative correlation of the degradation rates will have to take into account the various stressors in the field including temperature, relative humidity, start/stops and voltage cycles.
Date: July 1, 2011
Creator: Mukundan, Rangachary; James, Greg; Davey, John; Langlois, David; Torraco, Dennis; Yoon, Wonseok et al.
Object Type: Article
System: The UNT Digital Library
Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report (open access)

Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report

The injection of cold fluids into engineered geothermal system (EGS) and conventional geothermal reservoirs may be done to help extract heat from the subsurface or to maintain pressures within the reservoir (e.g., Rose et al., 2001). As these injected fluids move along fractures, they acquire heat from the rock matrix and remove it from the reservoir as they are extracted to the surface. A consequence of such injection is the migration of a cold-fluid front through the reservoir (Figure 1) that could eventually reach the production well and result in the lowering of the temperature of the produced fluids (thermal breakthrough). Efficient operation of an EGS as well as conventional geothermal systems involving cold-fluid injection requires accurate and timely information about thermal depletion of the reservoir in response to operation. In particular, accurate predictions of the time to thermal breakthrough and subsequent rate of thermal drawdown are necessary for reservoir management, design of fracture stimulation and well drilling programs, and forecasting of economic return. A potential method for estimating migration of a cold front between an injection well and a production well is through application of reactive tracer tests, using chemical whose rate of degradation is dependent on the reservoir …
Date: July 1, 2011
Creator: Plummer, Mitchell A.; Palmer, Carl D.; Mattson, Earl D.; Hull, Laurence C. & Redden, George D.
Object Type: Report
System: The UNT Digital Library
AIR QUALITY IMPACTS OF LIQUEFIED NATURAL GAS IN THE SOUTH COAST AIR BASIN OF CALIFORNIA (open access)

AIR QUALITY IMPACTS OF LIQUEFIED NATURAL GAS IN THE SOUTH COAST AIR BASIN OF CALIFORNIA

The effects of liquefied natural gas (LNG) on pollutant emission inventories and air quality in the South Coast Air Basin of California were evaluated using recent LNG emission measurements by Lawrence Berkeley National Laboratory and the Southern California Gas Company (SoCalGas), and with a state-of-the-art air quality model. Pollutant emissions can be affected by LNG owing to differences in composition and physical properties, including the Wobbe index, a measure of energy delivery rate. This analysis uses LNG distribution scenarios developed by modeling Southern California gas flows, including supplies from the LNG receiving terminal in Baja California, Mexico. Based on these scenarios, the projected penetratino of LNG in the South Coast Air Basin is expected to be limited. In addition, the increased Wobbe index of delivered gas (resulting from mixtures of LNG and conventional gas supplies) is expected to cause increases smaller than 0.05 percent in overall (area-wide) emissions of nitrogen oxides (NOx). BAsed on the photochemical state of the South Coast Air Basin, any increase in NOx is expected to cause an increase in the highest local ozone concentrations, and this is reflected in model results. However, the magnitude of the increase is well below the generally accepted accuracy of …
Date: July 1, 2011
Creator: Carerras-Sospedra, Marc; Brouwer, Jack; Dabdub, Donald; Lunden, Melissa & Singer, Brett
Object Type: Report
System: The UNT Digital Library

Allocating Reserve Requirements

This presentation provides an overview of present and possible future ways to allocate and assign benefits for reserve requirements.
Date: July 1, 2011
Creator: Milligan, M.; Kirby, B. & King, J.
Object Type: Presentation
System: The UNT Digital Library
Amorphous Indium-Zinc-Oxide Transparent Conductors for Thin Film PV: Preprint (open access)

Amorphous Indium-Zinc-Oxide Transparent Conductors for Thin Film PV: Preprint

Amorphous InZnO's (a-IZO) basic PV applicability has now been demonstrated in prototype CIGS, Si Heterojunction (SiHJ) and organic photovoltaics (OPV). However, to move beyond initial demonstration devices, improved TCO properties and processibility of the a-IZO films are needed. Here, RF-superimposed DC sputtering was used to improve the reliable deposition of a-IZO with conductivity > 3000 S/cm.
Date: July 1, 2011
Creator: Perkins, J.; Gennett, T.; Galante, M.; Gillaspie, D. & Ginley, D.
Object Type: Article
System: The UNT Digital Library
Analysis of HOM Properties of Superconducting Parallel-Bar Deflecting/Crabbing Cavities (open access)

Analysis of HOM Properties of Superconducting Parallel-Bar Deflecting/Crabbing Cavities

The superconducting parallel-bar cavity is currently being considered for a number of deflecting and crabbing applications due to improved properties and compact design geometries. The 499 MHz deflecting cavity proposed for the Jefferson Lab 12 GeV upgrade and the 400 MHz crab cavity for the proposed LHC luminosity upgrade are two of the major applications. For high current applications the higher order modes must be damped to acceptable levels to eliminate any beam instabilities. The frequencies and R/Q of the HOMs and mode separation are evaluated and compared for different parallel-bar cavity designs.
Date: July 1, 2011
Creator: S.U. De Silva, J.R. Delayen
Object Type: Article
System: The UNT Digital Library
Ashcroft v. al-Kidd: Official Immunity and Material Witnesses Before the Supreme Court (open access)

Ashcroft v. al-Kidd: Official Immunity and Material Witnesses Before the Supreme Court

This report discusses about Ashcroft v. al-Kidd: Official Immunity and Material Witnesses Before the Supreme Court.
Date: July 1, 2011
Creator: Doyle, Charles
Object Type: Report
System: The UNT Digital Library
Assessment of Indoor Air Quality Benefits and Energy Costs of Mechanical Ventilation (open access)

Assessment of Indoor Air Quality Benefits and Energy Costs of Mechanical Ventilation

Intake of chemical air pollutants in residences represents an important and substantial health hazard. Sealing homes to reduce air infiltration can save space conditioning energy, but can also increase indoor pollutant concentrations. Mechanical ventilation ensures a minimum amount of outdoor airflow that helps reduce concentrations of indoor emitted pollutants while requiring some energy for fan(s) and thermal conditioning of the added airflow. This work demonstrates a physics based, data driven modeling framework for comparing the costs and benefits of whole-house mechanical ventilation and applied the framework to new California homes. The results indicate that, on a population basis, the health benefits from reduced exposure to indoor pollutants in New California homes are worth the energy costs of adding mechanical ventilation as specified by ASHRAE Standard 62.2.This study determines the health burden for a subset of pollutants in indoor air and the costs and benefits of ASHRAE's mechanical ventilation standard (62.2) for new California homes. Results indicate that, on a population basis, the health benefits of new home mechanical ventilation justify the energy costs.
Date: July 1, 2011
Creator: Logue, J. M.; Price, P. N.; Sherman, M. H. & Singer, B. C.
Object Type: Article
System: The UNT Digital Library
Asymmetry and Risk (open access)

Asymmetry and Risk

None
Date: July 1, 2011
Creator: Goodwin, B T
Object Type: Article
System: The UNT Digital Library
Automated Demand Response Technology Demonstration Project for Small and Medium Commercial Buildings (open access)

Automated Demand Response Technology Demonstration Project for Small and Medium Commercial Buildings

Small and medium commercial customers in California make up about 20-25% of electric peak load in California. With the roll out of smart meters to this customer group, which enable granular measurement of electricity consumption, the investor-owned utilities will offer dynamic prices as default tariffs by the end of 2011. Pacific Gas and Electric Company, which successfully deployed Automated Demand Response (AutoDR) Programs to its large commercial and industrial customers, started investigating the same infrastructures application to the small and medium commercial customers. This project aims to identify available technologies suitable for automating demand response for small-medium commercial buildings; to validate the extent to which that technology does what it claims to be able to do; and determine the extent to which customers find the technology useful for DR purpose. Ten sites, enabled by eight vendors, participated in at least four test AutoDR events per site in the summer of 2010. The results showed that while existing technology can reliably receive OpenADR signals and translate them into pre-programmed response strategies, it is likely that better levels of load sheds could be obtained than what is reported here if better understanding of the building systems were developed and the DR response …
Date: July 1, 2011
Creator: Page, Janie; Kiliccote, Sila; Dudley, Junqiao Han; Piette, Mary Ann; Chiu, Albert K.; Kellow, Bashar et al.
Object Type: Report
System: The UNT Digital Library
Basic Wind Tech Course - Lesson Plans and Activities (open access)

Basic Wind Tech Course - Lesson Plans and Activities

The funds from this project were used to purchase tools and instrumentation to help replicate actual on-the-job wind energy scenarios which provided the students with the practical or applied components of wind energy jobs. This project enhanced the educational experiences provided for the students in terms of engineering and science components of wind energy by using electronics, control systems, and electro-mechanical instrumentation to help students learn standardized wind-specific craftsman skills. In addition the tools and instrumentation helped the students learn the safety necessary to work in the wind industry.
Date: July 1, 2011
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Basin scale assessment of gas hydrate dissociation in response to climate change (open access)

Basin scale assessment of gas hydrate dissociation in response to climate change

Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating climate. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those now occurring in the arctic and those predicted under future climate change scenarios, has only recently been investigated. Field investigations have discovered substantial methane gas plumes exiting the seafloor along the Arctic Ocean margin, and the plumes appear at depths corresponding to the upper limit of a receding gas hydrate stability zone. It has been suggested that these plumes may be the first visible signs of the dissociation of shallow hydrate deposits due to ongoing climate change in the arctic. We simulate the release of methane from oceanic deposits, including the effects of fully-coupled heat transfer, fluid flow, hydrate dissociation, and other thermodynamic processes, for systems representative of segments of the Arctic Ocean margins. The modeling encompasses a range of shallow hydrate deposits from the landward limit of the hydrate stability zone down to water depths beyond the expected range of century-scale temperature changes. We impose temperature changes corresponding to predicted rates of climate change-related ocean warming and examine the possibility of hydrate …
Date: July 1, 2011
Creator: Reagan, M.; Moridis, G.; Elliott, S.; Maltrud, M. & Cameron-Smith, P.
Object Type: Article
System: The UNT Digital Library
Biofuels Incentives: A Summary of Federal Programs (open access)

Biofuels Incentives: A Summary of Federal Programs

This report outlines federal programs that provide direct or indirect incentives for biofuels. For each program described, the report provides details including the administering agency, authorizing statute(s), annual funding, and expiration date. The Appendix provides summary information in a table format.
Date: July 1, 2011
Creator: Yacobucci, Brent D.
Object Type: Report
System: The UNT Digital Library
Calcium promotes cadmium elimination as vaterite grains by tobacco trichomes (open access)

Calcium promotes cadmium elimination as vaterite grains by tobacco trichomes

In tobacco plants, elimination of Zn and Cd via the production of Ca-containing grains at the top of leaf hairs, called trichomes, is a potent detoxification mechanism. This study examines how Cd is incorporated in these biominerals, and how calcium growth supplement modifies their nature. Scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDX), microfocused X-ray diffraction ({mu}-XRD), and microfocused X-ray absorption near edge structure ({mu}-XANES) spectroscopy were used to image the morphology of the grains, identify the crystallized mineral phases, and speciate Cd, respectively. The mineralogy of the grains and chemical form of Cd varied with the amount of Ca. When tobacco plants were grown in a nutrient solution containing 25 {micro}M Cd and low Ca supplement (Ca/Cd = 11 mol ratio), most of the grains were oblong-shaped and low-Cd-substituted calcite. When exposed to the same amount of Cd and high Ca supplement (Ca/Cd = 131 mol ratio), grains were more abundant and diverse in compositions, and in total more Cd was eliminated. Most grains in the high Ca/Cd experiment were round-shaped and composed predominantly of Cd-substituted vaterite, a usually metastable calcium carbonate polymorph, and subordinate calcite. Calcium oxalate and a Ca amorphous phase were detected occasionally in …
Date: July 1, 2011
Creator: Isaure, Marie-Pierre; Sarret, Geraldine; Harada, Emiko; Choi, Yong-Eui; Marcus, Matthew A.; Fakra, Sirine C. et al.
Object Type: Article
System: The UNT Digital Library
Calibration of the Accuscan II IN Vivo System for High Energy Lung Counting (open access)

Calibration of the Accuscan II IN Vivo System for High Energy Lung Counting

This report describes the April 2011 calibration of the Accuscan II HpGe In Vivo system for high energy lung counting. The source used for the calibration was a NIST traceable lung set manufactured at the University of Cincinnati UCLL43AMEU & UCSL43AMEU containing Am-241 and Eu-152 with energies from 26 keV to 1408 keV. The lung set was used in conjunction with a Realistic Torso phantom. The phantom was placed on the RMC II counting table (with pins removed) between the v-ridges on the backwall of the Accuscan II counter. The top of the detector housing was positioned perpendicular to the junction of the phantom clavicle with the sternum. This position places the approximate center line of the detector housing with the center of the lungs. The energy and efficiency calibrations were performed using a Realistic Torso phantom (Appendix I) and the University of Cincinnati lung set. This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for high energy lung counting and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Ovard R. & Georgeson, David L.
Object Type: Report
System: The UNT Digital Library
Calibration of the Accuscan II In Vivo System for I-125 Thyroid Counting (open access)

Calibration of the Accuscan II In Vivo System for I-125 Thyroid Counting

This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-125 thyroid counting. The source used for the calibration was a DOE manufactured Am-241/Eu-152 source contained in a 22 ml vial BEA Am-241/Eu-152 RMC II-1 with energies from 26 keV to 344 keV. The center of the detector housing was positioned 64 inches from the vault floor. This position places the approximate center line of the detector housing at the center line of the source in the phantom thyroid tube. The energy and efficiency calibration were performed using an RMC II phantom (Appendix J). Performance testing was conducted using source BEA Am-241/Eu-152 RMC II-1 and Validation testing was performed using an I-125 source in a 30 ml vial (I-125 BEA Thyroid 002) and an ANSI N44.3 phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-125 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Ovard R. & Georgeson, David L.
Object Type: Report
System: The UNT Digital Library
Calibration of the Accuscan II In Vivo System for I-131 Thyroid Counting (open access)

Calibration of the Accuscan II In Vivo System for I-131 Thyroid Counting

This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-131 thyroid counting. The source used for the calibration was an Analytics mixed gamma source 82834-121 distributed in an epoxy matrix in a Wheaton Liquid Scintillation Vial with energies from 88.0 keV to 1836.1 keV. The center of the detectors was position 64-feet from the vault floor. This position places the approximate center line of the detectors at the center line of the source in the thyroid tube. The calibration was performed using an RMC II phantom (Appendix J). Validation testing was performed using a Ba-133 source and an ANSI N44.3 Phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibrations including verification counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-131 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Orval R. & Georgeson, David L.
Object Type: Report
System: The UNT Digital Library
CdS/CdTe Solar Cells Containing Directly Deposited CdSxTe1-x Alloy Layers: Preprint (open access)

CdS/CdTe Solar Cells Containing Directly Deposited CdSxTe1-x Alloy Layers: Preprint

A CdSxTe1-x layer forms by interdiffusion of CdS and CdTe during the fabrication of thin-film CdTe photovoltaic (PV) devices. The CdSxTe1-x layer is thought to be important because it relieves strain at the CdS/CdTe interface that would otherwise exist due to the 10% lattice mismatch between these two materials. Our previous work [1] has indicated that the electrical junction is located in this interdiffused CdSxTe1-x region. Further understanding, however, is essential to predict the role of this CdSxTe1-x layer in the operation of CdS/CdTe devices. In this study, CdSxTe1-x alloy films were deposited by radio-frequency (RF) magnetron sputtering and co-evaporation from CdTe and CdS sources. Both RF-magnetron-sputtered and co-evaporated CdSxTe1-x films of lower S content (x<0.3) have a cubic zincblende (ZB) structure akin to CdTe, whereas those of higher S content have a hexagonal wurtzite (WZ) structure like that of CdS. Films become less preferentially oriented as a result of a CdCl2 heat treatment (HT) at ~400 degrees C for 5 min. Films sputtered in a 1% O2/Ar ambient are amorphous as deposited, but show CdTe ZB, CdS WZ, and CdTe oxide phases after a CdCl2 HT. Films sputtered in O2 partial pressure have a much wider bandgap than expected. …
Date: July 1, 2011
Creator: Duenow, J. N.; Dhere, R. G.; Moutinho, H. R.; To, B.; Pankow, J. W.; Kuciauskas, D. et al.
Object Type: Article
System: The UNT Digital Library
Changing ventilation rates in U.S. offices: Implications for health, work performance, energy, and associated economics (open access)

Changing ventilation rates in U.S. offices: Implications for health, work performance, energy, and associated economics

This paper provides quantitative estimates of benefits and costs of providing different amounts of outdoor air ventilation in U.S. offices. For four scenarios that modify ventilation rates, we estimated changes in sick building syndrome (SBS) symptoms, work performance, short-term absence, and building energy consumption. The estimated annual economic benefits were $13 billion from increasing minimum ventilation rates (VRs) from 8 to 10 L/s per person, $38 billion from increasing minimum VRs from 8 to 15 L/s per person, and $33 billion from increasing VRs by adding outdoor air economizers for the 50% of the office floor area that currently lacks economizers. The estimated $0.04 billion in annual energy-related benefits of decreasing minimum VRs from 8 to 6.5 L/s per person are very small compared to the projected annual costs of $12 billion. Benefits of increasing minimum VRs far exceeded energy costs while adding economizers yielded health, performance, and absence benefits with energy savings.
Date: July 1, 2011
Creator: Fisk, William; Black, Douglas & Brunner, Gregory
Object Type: Article
System: The UNT Digital Library
Characterization of Large Grain Nb Ingot Microstructure Using OIM and Laue Methods (open access)

Characterization of Large Grain Nb Ingot Microstructure Using OIM and Laue Methods

Large grain niobium is being examined for fabricating superconducting radiofrequency cavities as an alternative to using rolled sheet with fine grains. It is desirable to know the grain orientations of a niobium ingot slice before fabrication, as this allows heterogeneous strain and surface roughness effects arising from etching to be anticipated. Characterization of grain orientations has been done using orientation imaging microscopy (OIM), which requires destructive extraction of pieces from an ingot slice. Use of a Laue camera allows nondestructive characterization of grain orientations, a process useful for evaluating slices and deformation during the manufacturing process. Five ingot slices from CBMM, Ningxia, and Heraeus are compared. One set of slices was deformed into a half cell and the deformation processes that cause crystal rotations have been investigated and compared with analytical predictions. The five ingot slices are compared in terms of their grain orientations and grain boundary misorientations, indicating no obvious commonalities, which suggests that grain orientations develop randomly during solidification.
Date: July 1, 2011
Creator: D. Kang, D.C. Baars, T.R. Bieler, G. Ciovati, C. Compton, T.L. Grimm, A.A. Kolka
Object Type: Article
System: The UNT Digital Library
Coated Particle Fuel and Deep Burn Program Monthly Highlights June 2011 (open access)

Coated Particle Fuel and Deep Burn Program Monthly Highlights June 2011

During FY 2011 the CP & DB Program will report Highlights on a monthly basis, but will no longer produce Quarterly Progress Reports. Technical details that were previously included in the quarterly reports will be included in the appropriate Milestone Reports that are submitted to FCRD Program Management. These reports will also be uploaded to the Deep Burn website. The Monthly Highlights report for May 2011, ORNL/TM-2011/126, was distributed to program participants on June 9, 2011. As reported previously, the final Quarterly for FY 2010, Deep Burn Program Quarterly Report for July - September 2010, ORNL/TM-2010/301, was announced to program participants and posted to the website on December 28, 2010. This report discusses the following: (1) Fuel Performance Modeling - Fuel Performance Analysis; (2) Thermochemical Data and Model Development - (a) Thermochemical Behavior, (b) Thermomechanical Modeling, (c) Actinide and Fission Product Transport; (3) TRU (transuranic elements) TRISO (tri-structural isotropic) Development - (a) TRU Kernel Development, (b) Coating Development; and (4) LWR Fully Ceramic Fuel - (a) FCM Fabrication Development, (b) FCM Irradiation Testing.
Date: July 1, 2011
Creator: Snead, Lance Lewis; Bell, Gary L & Besmann, Theodore M
Object Type: Report
System: The UNT Digital Library
Combination of CDF and D0 results on the mass of the top quark using up to 5.8~fb-1 of data (open access)

Combination of CDF and D0 results on the mass of the top quark using up to 5.8~fb-1 of data

We summarize the top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published Run I (1992--1996) measurements with the most precise published and preliminary Run II (2001--present) measurements using up to 5.8 fb{sup -1} of data, adding new analyses (the missing transverse energy plus jets analysis) and updating old ones. Taking uncertainty correlations into account, and adding in quadrature the statistical and systematic uncertainties, the resulting preliminary Tevatron average mass of the top quark is M{sub t} = 173.2 {+-} 0.9 GeV/c{sup 2}.
Date: July 1, 2011
Creator: Lancaster, Mark
Object Type: Report
System: The UNT Digital Library
Combined CDF and D0 Searches for the Standard Model Higgs Boson Decaying to Two Photons with up to 8.2 fb^-1 (open access)

Combined CDF and D0 Searches for the Standard Model Higgs Boson Decaying to Two Photons with up to 8.2 fb^-1

We combine results from CDF and D0's direct searches for the standard model (SM) Higgs boson (H) produced in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV, focusing on the decay H {yields} {gamma}{gamma}. We compute upper limits on the Higgs boson production cross section times the decay branching fraction in the range 100 &lt; m{sub H} &lt; 150 GeV/c{sup 2}, and we interpret the results in the context of the standard model. We use the MSTW08 parton distribution functions and the latest theoretical cross section predictions when testing for the presence of a SM Higgs boson. With datasets corresponding to 7.0 fb{sup -1} (CDF) and 8.2 fb{sup -1} (D0), the 95% C.L. upper limits on Higgs boson production is a factor of 10.5 times the SM cross section for a Higgs boson mass of 115 GeV/c{sup 2}.
Date: July 1, 2011
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Combined CDF and D0 Upper Limits on Standard Model Higgs Boson Production with up to 8.6 fb-1 of Data (open access)

Combined CDF and D0 Upper Limits on Standard Model Higgs Boson Production with up to 8.6 fb-1 of Data

We combine results from CDF and D0 on direct searches for the standard model (SM) Higgs boson (H) in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV. Compared to the previous Tevatron Higgs boson search combination more data have been added, additional channels have been incorporated, and some previously used channels have been reanalyzed to gain sensitivity. We use the MSTW08 parton distribution functions and the latest theoretical cross sections when comparing our limits to the SM predictions. With up to 8.2 fb{sup -1} of data analyzed at CDF and up to 8.6 fb{sup -1} at D0, the 95% C.L. our upper limits on Higgs boson production are factors of 1.17, 1.71, and 0.48 times the values of the SM cross section for Higgs bosons of mass m{sub H} = 115 GeV/c{sup 2}, 140 GeV/c{sup 2}, and 165 GeV/c{sup 2}, respectively. The corresponding median upper limits expected in the absence of Higgs boson production are 1.16, 1.16, and 0.57. There is a small ({approx} 1{sigma}) excess of data events with respect to the background estimation in searches for the Higgs boson in the mass range 125 &lt; m{sub H} &lt; 155 GeV/c{sup 2}. We exclude, at …
Date: July 1, 2011
Creator: CDF, The; Collaborations, D0; Phenomena, the Tevatron New & Group, Higgs Working
Object Type: Article
System: The UNT Digital Library