\ttbar and single top cross sections at the Tevatron (open access)

\ttbar and single top cross sections at the Tevatron

We present a summary of the latest measurements of the top pair and single top cross sections performed by the CDF and D0 collaborations at the Fermilab Tevatron collider. The Fermilab Tevatron collider ended its run on September 30, 2011 after delivering more than 10 fb{sup -1} of p{bar p} collision data per experiment at {radical}s = 1.96 TeV. A large sample of top quarks collected by the CDF and D0 experiments allows to perform precision measurements of their production which is predicted to occur within the standard model (SM) either in pairs via strong interactions or as single top events via electroweak interactions. Such measurements represent an important test of the theoretical calculations which predict the t{bar t} and single top production cross sections with a precision of 6% to 8% and 5%, respectively. Precise measurements of top pair cross section ({sigma}{sub t{bar t}}) in different t{bar t} final states and single top production via different production mechanisms are highly desirable as they are sensitive to the non-SM particles that may appear in top quark production or decays.
Date: January 1, 2012
Creator: CDF, Elizaveta Shabalina for & collaborations, D0
Object Type: Article
System: The UNT Digital Library
Turbine Inflow Characterization at the National Wind Technology Center: Preprint (open access)

Turbine Inflow Characterization at the National Wind Technology Center: Preprint

Utility-scale wind turbines operate in dynamic flows that can vary significantly over timescales from less than a second to several years. To better understand the inflow to utility-scale turbines, two inflow towers were installed and commissioned at the National Renewable Energy Laboratory's (NREL) National Wind Technology Center near Boulder, Colorado, in 2011. These towers are 135 m tall and instrumented with a combination of sonic anemometers, cup anemometers, wind vanes, and temperature measurements to characterize the inflow wind speed and direction, turbulence, stability and thermal stratification to two utility-scale turbines. Herein, we present variations in mean and turbulent wind parameters with height, atmospheric stability, and as a function of wind direction that could be important for turbine operation as well as persistence of turbine wakes. Wind speed, turbulence intensity, and dissipation are all factors that affect turbine performance. Our results shown that these all vary with height across the rotor disk, demonstrating the importance of measuring atmospheric conditions that influence wind turbine performance at multiple heights in the rotor disk, rather than relying on extrapolation from lower levels.
Date: January 1, 2012
Creator: Clifton, A.; Schreck, S.; Scott, G.; Kelley, N. & Lundquist, J.
Object Type: Article
System: The UNT Digital Library
Two-Point Correlator Fits on HISQ Ensembles (open access)

Two-Point Correlator Fits on HISQ Ensembles

None
Date: January 1, 2012
Creator: Bazavov, A.; Bernard, C.; Lightman, M.; Bouchard, C.; DeTar, C.; Foley, J. et al.
Object Type: Article
System: The UNT Digital Library
U.S. Department of Energy Solar Decathlon: Challenging Students to Build Energy Efficient, Cost-Effective, and Attractive Solar-Powered Houses (open access)

U.S. Department of Energy Solar Decathlon: Challenging Students to Build Energy Efficient, Cost-Effective, and Attractive Solar-Powered Houses

The U.S. Department of Energy Solar Decathlon challenges collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive. The winner of the competition is the team that best blends affordability, consumer appeal, and design excellence with optimal energy production and maximum efficiency. The paper discusses the solutions developed for the event. We believe that the solutions implemented for Solar Decathlon 2011 represent current trends and that by analyzing, critiquing, and exposing the solutions pursued, the industry can become better suited to address challenges of the future. Constructing a solar community using high-efficiency design and unique materials while remaining code compliant, safe, and effective results in solutions that are market relevant, important, and interesting to the industry as a whole.
Date: January 1, 2012
Creator: Simon, J.
Object Type: Article
System: The UNT Digital Library
U.S. Patent 8,304,670, Portable Weighing System with Alignment Features (open access)

U.S. Patent 8,304,670, Portable Weighing System with Alignment Features

A system for weighing a load is disclosed. The weighing system includes a pad having at least one transducer for weighing a load disposed on the pad. In some embodiments the pad has a plurality of foot members and the weighing system may include a plate that disposed underneath the pad for receiving the plurality of foot members and for aligning the foot members when the weighing system is installed. The weighing system may include a spacer disposed adjacent the pad and in some embodiments, a spacer anchor operatively secures the spacer to a support surface, such as a plate, a railway bed, or a roadway. In some embodiments the spacer anchor operatively secures both the spacer and the pad to a roadway.
Date: January 1, 2012
Creator: Abercrombie, Robert K; Richardson, Gregory; Scudiere, Matthew B & Sheldon, Frederick T
Object Type: Book
System: The UNT Digital Library
Understanding and predicting metallic whisker growth and its effects on reliability : LDRD final report. (open access)

Understanding and predicting metallic whisker growth and its effects on reliability : LDRD final report.

Tin (Sn) whiskers are conductive Sn filaments that grow from Sn-plated surfaces, such as surface finishes on electronic packages. The phenomenon of Sn whiskering has become a concern in recent years due to requirements for lead (Pb)-free soldering and surface finishes in commercial electronics. Pure Sn finishes are more prone to whisker growth than their Sn-Pb counterparts and high profile failures due to whisker formation (causing short circuits) in space applications have been documented. At Sandia, Sn whiskers are of interest due to increased use of Pb-free commercial off-the-shelf (COTS) parts and possible future requirements for Pb-free solders and surface finishes in high-reliability microelectronics. Lead-free solders and surface finishes are currently being used or considered for several Sandia applications. Despite the long history of Sn whisker research and the recently renewed interest in this topic, a comprehensive understanding of whisker growth remains elusive. This report describes recent research on characterization of Sn whiskers with the aim of understanding the underlying whisker growth mechanism(s). The report is divided into four sections and an Appendix. In Section 1, the Sn plating process is summarized. Specifically, the Sn plating parameters that were successful in producing samples with whiskers will be reviewed. In Section …
Date: January 1, 2012
Creator: Michael, Joseph Richard; Grant, Richard P.; Rodriguez, Mark Andrew; Pillars, Jamin; Susan, Donald Francis; McKenzie, Bonnie Beth et al.
Object Type: Report
System: The UNT Digital Library
Updated measurements of hadronic B decays at CDF (open access)

Updated measurements of hadronic B decays at CDF

The CDF experiment at the Tevatron p{bar p} collider established that extensive and detailed exploration of the b-quark dynamics is possible in hadron collisions, with results competitive and supplementary to those from e{sup +}e{sup -} colliders. This provides a rich, and highly rewarding program that has currently reached full maturity. In the following I report some recent results on hadronic decays: the evidence for the charmless annihilation decay mode B{sub s}{sup 0} {yields} {pi}{sup +}{pi}{sup -}, and the first reconstruction in hadron collisions of the suppressed decays B{sup -} {yields} D({yields} K{sup +}{pi}{sup 0})K{sup -} and B{sup -} {yields} D({yields} K{sup +} {pi}{sup -}){pi}{sup -}.
Date: January 1, 2012
Creator: Morello, Michael J.
Object Type: Article
System: The UNT Digital Library
Upper limits for the photoproduction cross section for the Phi--(1860) pentaquark state off the deuteron (open access)

Upper limits for the photoproduction cross section for the Phi--(1860) pentaquark state off the deuteron

We searched for the {Phi}{sup --}(1860) pentaquark in the photoproduction process off the deuteron in the {Xi}{sup -} {pi}{sup -} decay channel using CLAS. The invariant mass spectrum of the {Xi}{sup -} {pi}{sup -} system does not indicate any statistically significant enhancement near the reported mass M = 1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90% confidence level upper limit of 0.7 nb for the photoproduction cross section of {Phi}{sup --}(1860) with a consecutive decay into {Xi}{sup -} {pi}{sup -} in the photon energy range 4.5 GeV < E{sub {gamma}} < 5.5 GeV.
Date: January 1, 2012
Creator: Egiyan, Hovanes
Object Type: Article
System: The UNT Digital Library
Variance Analysis of Wind and Natural Gas Generation under Different Market Structures: Some Observations (open access)

Variance Analysis of Wind and Natural Gas Generation under Different Market Structures: Some Observations

Does large scale penetration of renewable generation such as wind and solar power pose economic and operational burdens on the electricity system? A number of studies have pointed to the potential benefits of renewable generation as a hedge against the volatility and potential escalation of fossil fuel prices. Research also suggests that the lack of correlation of renewable energy costs with fossil fuel prices means that adding large amounts of wind or solar generation may also reduce the volatility of system-wide electricity costs. Such variance reduction of system costs may be of significant value to consumers due to risk aversion. The analysis in this report recognizes that the potential value of risk mitigation associated with wind generation and natural gas generation may depend on whether one considers the consumer's perspective or the investor's perspective and whether the market is regulated or deregulated. We analyze the risk and return trade-offs for wind and natural gas generation for deregulated markets based on hourly prices and load over a 10-year period using historical data in the PJM Interconnection (PJM) from 1999 to 2008. Similar analysis is then simulated and evaluated for regulated markets under certain assumptions.
Date: January 1, 2012
Creator: Bush, B.; Jenkin, T.; Lipowicz, D.; Arent, D. J. & Cooke, R.
Object Type: Report
System: The UNT Digital Library
Vegetable Oil from Leaves and Stems: Vegetative Production of Oil in a C4 Crop (open access)

Vegetable Oil from Leaves and Stems: Vegetative Production of Oil in a C4 Crop

PETRO Project: Arcadia Biosciences, in collaboration with the University of California-Davis, is developing plants that produce vegetable oil in their leaves and stems. Ordinarily, these oils are produced in seeds, but Arcadia Biosciences is turning parts of the plant that are not usually harvested into a source of concentrated energy. Vegetable oil is a concentrated source of energy that plants naturally produce and is easily separated after harvest. Arcadia Biosciences will isolate traits that control oil production in seeds and transfer them into leaves and stems so that all parts of the plants are oil-rich at harvest time. After demonstrating these traits in a fast-growing model plant, Arcadia Biosciences will incorporate them into a variety of dedicated biofuel crops that can be grown on land not typically suited for food production
Date: January 1, 2012
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Vertex Sensitivity in the Schwinger-Dyson Equations of QCD (open access)

Vertex Sensitivity in the Schwinger-Dyson Equations of QCD

The nonperturbative gluon and ghost propagators in Landau gauge QCD are obtained using the Schwinger-Dyson equation approach. The propagator equations are solved in Euclidean space using Landau gauge with a range of vertex inputs. Initially we solve for the ghost alone, using a model gluon input, which leads us to favour a finite ghost dressing in the nonperturbative region. In order to then solve the gluon and ghost equations simultaneously, we find that non-trivial vertices are required, particularly for the gluon propagator in the small momentum limit. We focus on the properties of a number vertices and how these differences influence the final solutions. The self-consistent solutions we obtain are all qualitatively similar and contain a mass-like term in the gluon propagator dressing in agreement with related studies, supporting the long-held proposal of Cornwall.
Date: January 1, 2012
Creator: David J. Wilson, Michael R. Pennington
Object Type: Article
System: The UNT Digital Library
Waters, Seas and Wine: Science for Successful Climate Adaptation (open access)

Waters, Seas and Wine: Science for Successful Climate Adaptation

is a growing demand for adaptation science as a vehicle for delivering critical knowledge to public and private organizations that are attempting to adapt to the changing climate. This expansion of adaptation science is occurring, however, in the absence of a robust understanding of how that science can or should contribute to successful adaptation. For the adaptation science enterprise to be successful, it must provide knowledge that has value to adaptation actors. Accomplishing this objective, however, often requires more than just research, and, in fact, may necessitate new cultural perspectives regarding the role of science in public policy as well as new kinds of researchers and research institutions. These issues are explored through a series of case studies from Australia and the United Kingdom that illustrate the various ways in which adaptation science engages with adaptation processes and the extent to which that science can be judged as successful. The case studies demonstrate that there are multiple pathways by which adaptation science can be successful, depending on the knowledge that is needed by a particular actor at a particular stage in the adaptation process. Nevertheless, there are significant opportunities for the more explicit alignment of the needs of decision-makers and …
Date: January 1, 2012
Creator: Preston, Benjamin L
Object Type: Book
System: The UNT Digital Library
Weatherization Innovation Pilot Program: Program Overview and Philadelphia Project Highlight (Fact Sheet) (open access)

Weatherization Innovation Pilot Program: Program Overview and Philadelphia Project Highlight (Fact Sheet)

Case Study with WIPP program overview, information regarding eligibility, and successes from Pennsylvania's Commission on Economic Opportunity (CEO) that demonstrate innovative approaches that maximize the benefit of the program. The Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) recently launched the Weatherization Innovation Pilot Program (WIPP) to accelerate innovations in whole-house weatherization and advance DOE's goal of increasing the energy efficiency and health and safety of homes of low-income families. Since 2010, WIPP has helped weatherization service providers as well as new and nontraditional partners leverage non-federal financial resources to supplement federal grants, saving taxpayer money. WIPP complements the Weatherization Assistance program (WAP), which operates nation-wide, in U.S. territories and in three Native American tribes. 16 grantees are implementing weatherization innovation projects using experimental approaches to find new and better ways to weatherize homes. They are using approaches such as: (1) Financial tools - by understanding a diverse range of financing mechanisms, grantees can maximize the impact of the federal grant dollars while providing high-quality work and benefits to eligible low-income clients; (2) Green and healthy homes - in addition to helping families reduce their energy costs, grantees can protect their health and safety. Two WIPP …
Date: January 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Western Region Renewable Energy Markets: Implications for the Bureau of Land Management (open access)

Western Region Renewable Energy Markets: Implications for the Bureau of Land Management

The purpose of this analysis is to provide the U.S. Department of the Interior (DOI) and the Bureau of Land Management (BLM) with an overview of renewable energy (RE) generation markets, transmission planning efforts, and the ongoing role of the BLM RE projects in the electricity markets of the 11 states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming) that comprise the Western Electricity Coordinating Council (WECC) Region. This analysis focuses on the status of, and projections for, likely development of non-hydroelectric renewable electricity from solar (including photovoltaic [PV] and concentrating solar power [CSP]), wind, biomass and geothermal resources in these states. Absent new policy drivers and without the extension of the DOE loan guarantee program and Treasury's 1603 program, state RPS requirements are likely to remain a primary driver for new RE deployment in the western United States. Assuming no additional policy incentives are implemented, projected RE demand for the WECC states by 2020 is 134,000 GWh. Installed capacity to meet that demand will need to be within the range of 28,000-46,000 MW.
Date: January 1, 2012
Creator: Haase, S.; Billman, L. & Gelman, R.
Object Type: Report
System: The UNT Digital Library
What then do we do about computer security? (open access)

What then do we do about computer security?

This report presents the answers that an informal and unfunded group at SNL provided for questions concerning computer security posed by Jim Gosler, Sandia Fellow (00002). The primary purpose of this report is to record our current answers; hopefully those answers will turn out to be answers indeed. The group was formed in November 2010. In November 2010 Jim Gosler, Sandia Fellow, asked several of us several pointed questions about computer security metrics. Never mind that some of the best minds in the field have been trying to crack this nut without success for decades. Jim asked Campbell to lead an informal and unfunded group to answer the questions. With time Jim invited several more Sandians to join in. We met a number of times both with Jim and without him. At Jim's direction we contacted a number of people outside Sandia who Jim thought could help. For example, we interacted with IBM's T.J. Watson Research Center and held a one-day, videoconference workshop with them on the questions.
Date: January 1, 2012
Creator: Suppona, Roger A.; Mayo, Jackson R.; Davis, Christopher Edward; Berg, Michael J. & Wyss, Gregory Dane
Object Type: Report
System: The UNT Digital Library
Wind energy Computerized Maintenance Management System (CMMS) : data collection recommendations for reliability analysis. (open access)

Wind energy Computerized Maintenance Management System (CMMS) : data collection recommendations for reliability analysis.

This report addresses the general data requirements for reliability analysis of fielded wind turbines and other wind plant equipment. The report provides a rationale for why this data should be collected, a list of the data needed to support reliability and availability analysis, and specific data recommendations for a Computerized Maintenance Management System (CMMS) to support automated analysis. This data collection recommendations report was written by Sandia National Laboratories to address the general data requirements for reliability analysis of operating wind turbines. This report is intended to help develop a basic understanding of the data needed for reliability analysis from a Computerized Maintenance Management System (CMMS) and other data systems. The report provides a rationale for why this data should be collected, a list of the data needed to support reliability and availability analysis, and specific recommendations for a CMMS to support automated analysis. Though written for reliability analysis of wind turbines, much of the information is applicable to a wider variety of equipment and analysis and reporting needs. The 'Motivation' section of this report provides a rationale for collecting and analyzing field data for reliability analysis. The benefits of this type of effort can include increased energy delivered, decreased …
Date: January 1, 2012
Creator: Peters, Valerie A. & Ogilvie, Alistair B.
Object Type: Report
System: The UNT Digital Library
X-Ray and Neutron Diffuse Scattering Measurements (open access)

X-Ray and Neutron Diffuse Scattering Measurements

None
Date: January 1, 2012
Creator: Ice, Gene E
Object Type: Book
System: The UNT Digital Library