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Azimuthal anisotropy: The higher harmonics

Description: We report the first observations of the fourth harmonic (v{sub 4}) in the azimuthal distribution of particles at RHIC. The measurement was done taking advantage of the large elliptic flow generated at RHIC. The integrated v{sub 4} is about a factor of 10 smaller than v{sub 2}. For the sixth (v{sub 6}) and eighth (v{sub 8}) harmonics upper limits on the magnitudes are reported.
Date: March 12, 2004
Creator: Poskanzer, Arthur M. & Collaboration, STAR
Partner: UNT Libraries Government Documents Department

Counts of low-Redshift SDSS quasar candidates

Description: We analyze the counts of low-redshift quasar candidates selected using nine-epoch SDSS imaging data. The co-added catalogs are more than 1 mag deeper than single-epoch SDSS data, and allow the selection of low-redshift quasar candidates using UV-excess and also variability techniques. The counts of selected candidates are robustly determined down to g = 21.5. This is about 2 magnitudes deeper than the position of a change in the slope of the counts reported by Boyle et al. (1990, 2000) for a sample selected by UV-excess, and questioned by Hawkins & Veron (1995), who utilized a variability-selected sample. Using SDSS data, we confirm a change in the slope of the counts for both UV-excess and variability selected samples, providing strong support for the Boyle et al. results.
Date: March 12, 2004
Creator: al., Zeljko Ivezic et
Partner: UNT Libraries Government Documents Department

Conditions necessary for capillary hysteresis in porous media: Tests of grain-size and surface tension influences

Description: Hysteresis in the relation between water saturation and matric potential is generally regarded as a basic aspect of unsaturated porous media. However, the nature of an upper length scale limit for saturation hysteresis has not been previously addressed. Since hysteresis depends on whether or not capillary rise occurs at the grain scale, this criterion was used to predict required combinations of grain size, surface tension, fluid-fluid density differences, and acceleration in monodisperse systems. The Haines number (Ha), composed of the aforementioned variables, is proposed as a dimensionless number useful for separating hysteretic (Ha < 15) versus nonhysteretic (Ha > 15) behavior. Vanishing of hysteresis was predicted to occur for grain sizes greater than 10.4 +- 0.5 mm, for water-air systems under the acceleration of ordinary gravity, based on Miller-Miller scaling and Haines' original model for hysteresis. Disappearance of hysteresis was tested through measurements of drainage and wetting curves of sands and gravels and occurs between grain sizes of 10 and 14 mm (standard conditions). The influence of surface tension was tested through measurements of moisture retention in 7 mm gravel, without and with a surfactant (sodium dodecylbenzenesulfonate (SDBS)). The ordinary water system (Ha = 7) exhibited hysteresis, while the SDBS system (Ha = 18) did not. The experiments completed in this study indicate that hysteresis in moisture retention relations has an upper limit at Ha = 16 +- 2 and show that hysteresis is not a fundamental feature of unsaturated porous media.
Date: March 12, 2004
Creator: Tokunaga, Tetsu K.; Olson, Keith R. & Wan, Jiamin
Partner: UNT Libraries Government Documents Department

D(S) spectrum and leptonic decays with Fermilab heavy quarks and improved staggered light quarks

Description: We present preliminary results for the D{sub s} meson spectrum and decay constants in unquenched lattice QCD. Simulations are carried out with 2 + 1 dynamical quarks using gauge configurations generated by the MILC collaboration. We use the ''asqtad'' a{sup 2} improved staggered action for the light quarks, and the clover heavy quark action with the Fermilab interpretation. We compare our spectrum results with the newly discovered 0{sup +} and 1{sup +} states in the D{sub s} system.
Date: March 12, 2004
Creator: al., Massimo Di Pierro et
Partner: UNT Libraries Government Documents Department

A Measure of the goodness of fit in unbinned likelihood fits; end of Bayesianism?

Description: Maximum likelihood fits to data can be done using binned data (histograms) and unbinned data. With binned data, one gets not only the fitted parameters but also a measure of the goodness of fit. With unbinned data, currently, the fitted parameters are obtained but no measure of goodness of fit is available. This remains, to date, an unsolved problem in statistics. Using Bayes' theorem and likelihood ratios, they provide a method by which both the fitted quantities and a measure of the goodness of fit are obtained for unbinned likelihood fits, as well as errors in the fitted quantities. The quantity, conventionally interpreted as a Bayesian prior, is seen in this scheme to be a number not a distribution, that is determined from data.
Date: March 12, 2004
Creator: Raja, Rajendran
Partner: UNT Libraries Government Documents Department

Aluminum Leaching of ''Archived'' Sludge from Tanks 8F, 11H, and 12H

Description: Aluminum can promote formation or dissolution of networks in hydroxide solid solutions. When present in large amounts it will act as a network former increasing both the viscosity and the surface tension of melts. This translates into poor free flow properties that affect pour rate of glass production in the Defense Waste Processing Facility (DWPF). To mitigate this situation, DWPF operations limit the amount of aluminum contained in sludge. This study investigated the leaching of aluminum compounds from archived sludge samples. The conclusions found boehmite present as the predominant aluminum compound in sludge from two tanks. We did not identify an aluminum compound in sludge from the third tank. We did not detect any amorphous aluminum hydroxide in the samples. The amount of goethite measured 4.2 percentage weight while hematite measured 3.7 percentage weight in Tank 11H sludge. The recommended recipe for removing gibbsite in sludge proved inefficient for digesting boehmite, removing less than 50 per cent of the compound within 48 hours. The recipe did remove boehmite when the test ran for 10 days (i.e., 7 more days than the recommended baseline leaching period). Additions of fluoride and phosphate to Tank 12H archived sludge did not improve the aluminum leaching efficiency of the baseline recipe.
Date: March 12, 2004
Creator: Fondeur, Fernando F.; Hobbs, D. T. & Fink, S. D.
Partner: UNT Libraries Government Documents Department

Computational investigation of unusual behavior in certain capillary tubes

Description: We investigate computationally two recent mathematical findings involving unusual behavior of solutions of the Young-Laplace capillary equation in cylindrical tubes of particular sections. The first concerns a configuration for which smoothing of the boundary curve at a sharp corner leads from existence to non-existence of a solution over the container section in zero gravity. The second describes a discontinuous behavior of relative rise height in nesting tubes placed vertically in an infinite reservoir. The numerical results support and quantify the mathematical predictions.
Date: March 12, 2004
Creator: Brady, Victor; Concus, Paul & Finn, Robert
Partner: UNT Libraries Government Documents Department

Theta13 Neutrino Experiment at the Diablo Canyon Power Plant, LBNL Engineering Summary Report

Description: This summary document describes the results of conceptual design and cost estimates performed by LBNL Engineering staff between October 10, 2003 and March 12, 2004 for the proposed {theta}{sub 13} neutrino experiment at the Diablo Canyon Power Plant (DCPP). This document focuses on the detector room design concept and mechanical engineering issues associated with the neutrino detector structures. Every effort has been made not to duplicate information contained in the last LBNL Engineering Summary Report dated October 10, 2003. Only new or updated information is included in this document.
Date: March 12, 2004
Creator: Oshatz, Daryl
Partner: UNT Libraries Government Documents Department

Volume-limited SDSS/First quasars and the radio dichotomy

Description: Much evidence has been presented in favor of and against the existence of two distinct populations of quasars, radio-loud and radio-quiet. The SDSS differs from earlier optically selected quasar surveys in the large number of quasars and the targeting of FIRST radio source counterparts as quasar candidates. This allows a qualitatively different approach of constructing a series of samples at different redshifts which are volume-limited with respect to both radio and optical luminosity. This technique avoids any biases from the strong evolution of quasar counts with redshift and potential redshift-dependent selection effects. We find that optical and radio luminosities of quasars detected in both SDSS and FIRST are not well correlated within each redshift shell, although the fraction of radio detections among optically selected quasars remains roughly constant at 10% for z {le} 3.2. The distribution in the luminosity-luminosity plane does not appear to be strongly bimodal. The optical luminosity function is marginally flatter at higher radio luminosities.
Date: March 12, 2004
Creator: Jester, Sebastian & Kron, R.G.
Partner: UNT Libraries Government Documents Department

Development of a Charged Particle Microbeam for Targeted and Single Particle Subcellular Irradiation

Description: The development of a charged particle microbeam for single particle, subcellular irradiations at the Massachusetts Institute of Technology Laboratory for Accelerator Beam Applications (MIT LABA) was initiated under this NEER aeard. The Microbeam apparatus makes use of a pre-existing electrostatic accelerator with a horizontal beam tube.
Date: March 12, 2004
Creator: Yanch, Jacquelyn C.
Partner: UNT Libraries Government Documents Department

Comparison of Australian and US Cost-Benefit Approaches to MEPS

Description: The Australian Greenhouse Office contracted with the Collaborative Labeling and Appliance Standards Program (CLASP) for LBNL to compare US and Australian approaches to analyzing costs and benefits of minimum energy performance standards (MEPS). This report compares the approaches for three types of products: household refrigerators and freezers, small electric storage water heaters, and commercial/industrial air conditioners. This report presents the findings of similarities and differences between the approaches of the two countries and suggests changes to consider in the approach taken in Australia. The purpose of the Australian program is to reduce greenhouse gas emissions, while the US program is intended to increase energy efficiency; each program is thus subject to specific constraints. The market and policy contexts are different, with the USA producing most of its own products and conducting pioneering engineering-economic studies to identify maximum energy efficiency levels that are technologically feasible and economically justified. In contrast, Australia imports a large share of its products and adopts MEPS already in place elsewhere. With these differences in circumstances, Australia's analysis approach could be expected to have less analytical detail and still result in MEPS levels that are appropriate for their policy and market context. In practice, the analysis required to meet these different objectives is quite similar. To date, Australia's cost-benefit analysis has served the goals and philosophies of the program well and been highly effective in successfully identifying MEPS that are significantly reducing greenhouse gas emissions while providing economic benefits to consumers. In some cases, however, the experience of the USA--using more extensive data sets and more detailed analysis--suggests possible improvements to Australia's cost-benefit analysis. The principal findings of the comparison are: (1) The Technology and Market Assessments are similar; no changes are recommended. (2) The Australian approach to determining the relationship of price to energy efficiency is ...
Date: March 12, 2004
Creator: McMahon, James E.
Partner: UNT Libraries Government Documents Department

Contract Management: Agencies Can Achieve Significant Savings on Purchase Card Buys

Description: A letter report issued by the General Accounting Office with an abstract that begins "From 1994 to 2003, the use of government purchase cards exploded from $1 billion to $16 billion. Most purchase card transactions are for small purchases, less than $2,500. While agencies estimate that using purchase cards saves hundreds of millions of dollars in administrative costs, the rapid growth of the purchase card presents opportunities for agencies to negotiate discounts with major vendors, thereby better leveraging agencies' buying power. To discover whether agencies were doing this, we examined program management and cardholder practices at the Departments of Agriculture, Army, Navy, Air Force, Interior, Justice, Transportation, and Veterans Affairs. GAO also examined why agencies may not have explored these opportunities."
Date: March 12, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Summary Analysis of Federal Commercial Aviation Taxes and Fees

Description: Correspondence issued by the General Accounting Office with an abstract that begins "For 2001 through the third quarter of 2003, the U.S. airline industry reported operating losses of $20.7 billion. A number of factors--including the economic slowdown, a shift in business travel buying behavior, and the aftermath of the September 11, 2001, terrorist attacks--contributed to these losses by reducing passenger and cargo volumes and depressing fares. To improve their financial position, many airlines cut costs by various means, notably by reducing labor expenditures and by decreasing capacity through cutting flight frequencies, using smaller aircraft, or eliminating service to some communities. Carriers have also reduced some airfares to encourage travel. Despite these efforts, several airlines filed for bankruptcy protection. It remains to be seen when the industry will emerge from this downturn. In response to the industry's financial condition, Congress has provided several forms of financial relief. In September 2001, Congress passed the Air Transportation Safety and System Stabilization Act, which authorized payments of up to $4.5 billion in pretax cash assistance to reimburse air carriers for losses incurred as a direct result of the 4-day government shut-down of air traffic and incremental losses stemming from the terrorist attacks and also authorized up to $10 billion in loan guarantees to help airlines gain emergency access to capital. In January 2002, Congress appropriated $100 million for new or modified cockpit doors on commercial aircraft to improve security of the flight deck. In the fiscal year 2003 supplemental appropriations act, Congress appropriated $2.4 billion in security cost relief for airlines. To provide information to Congress for its continuing deliberations about whether and, if so, how to provide additional help to the airline industry, we reviewed the payments of major commercial aviation taxes and fees over the last 5 years. The federal government levies ...
Date: March 12, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

A Free Trade Area of the Americas: Status of Negotiations and Major Policy Issues

Description: In 1994, 34 Western Hemisphere nations met at the first Summit of the Americas, envisioning a plan for a Free Trade Area of the Americas (FTAA) by January 2005. Nine years later, the third draft text of the agreement was presented at the Miami trade ministerial held November 20-21, 2003. Deep differences remain unresolved, however, and, as reflected in the Ministerial Declaration, have taken the FTAA in a new direction. It calls for a two-tier framework comprising a set of “common rights and obligations” for all countries, augmented by voluntary plurilateral arrangements with country benefits related to commitments. A follow-up meeting in Puebla, Mexico was unable to clarify the details of this arrangement and negotiations will continue in late April 2004, when it is hoped that specific commitments will be defined. This report provides background and analysis for Congress on the proposed FTAA and will be updated.
Date: March 12, 2004
Creator: Hornbeck, J. F.
Partner: UNT Libraries Government Documents Department

Prescription Drug Coverage Under Medicaid

Description: Medicaid is a joint federal-state entitlement program that pays for medical services on behalf of certain groups of low-income persons. It is the third largest social program in the federal budget, exceeded only by Social Security and Medicare and is typically the second largest spending item for states. This report discusses prescription drug policies under the program.
Date: March 12, 2004
Creator: Hearne, Jean & Grady, April
Partner: UNT Libraries Government Documents Department

Fishery, Aquaculture, and Marine Mammal Legislation in the 108th Congress

Description: This report discusses policy and legislation regarding fish and marine mammals. These animals are important resources in open ocean and nearshore coastal areas. Commercial and sport fishing are jointly managed by the federal government and individual states. Many laws and regulations guide the management of these resources by federal agencies.
Date: March 12, 2004
Creator: Buck, Eugene H.
Partner: UNT Libraries Government Documents Department

Polishing slurry induced surface haze on phosphate laser glasses

Description: The effects of residual polishing slurry on the surface topology of highly-polished, Nd-doped metaphosphate laser glasses are reported. Glass samples were pitched polished using cerium oxide or zirconium oxide slurry at different pHs and then washed by different methods that allowed varying amounts of residual slurry to ''dry'' on the surface. Upon re-washing with water, some of the samples showed surface haze (scatter), which scaled with the amount of residual slurry. Profilometry measurements showed that the haze is the result of shallow surface pits (100 nm - 20 {micro}m wide x {approx}15 nm deep). Chemical analyses of material removed during rewashing, confirmed the removal of glass components as well as the preferential removal of modifier ions (e.g. K{sup 1+} and Mg{sup 2+}). The surface pits appear to result from reaction of the glass with condensed liquid at the slurry particle-glass interface that produces water-soluble phosphate products that dissolves away with subsequent water contact. Aggressive washing, to remove residual slurry immediately following polishing, can minimize surface haze on phosphate glasses. It is desirable to eliminate haze from glass used in high-peak-power lasers, since it can cause scatter-induced optical modulation that can cause damage to downstream optics.
Date: March 12, 2004
Creator: Suratwala, T I; Miller, P E; Ehrmann, P R & Steele, R A
Partner: UNT Libraries Government Documents Department