Evidence for the Absence of Gluon Orbital Angular Momentum in the Nucleon (open access)

Evidence for the Absence of Gluon Orbital Angular Momentum in the Nucleon

The Sivers mechanism for the single-spin asymmetry in unpolarized lepton scattering from a transversely polarized nucleon is driven by the orbital angular momentum carried by its quark and gluon constituents, combined with QCD final-state interactions. Both quark and gluon mechanisms can generate such a single-spin asymmetry, though only the quark mechanism can explain the small single-spin asymmetry measured by the COMPASS collaboration on the deuteron, suggesting the gluon mechanism is small relative to the quark mechanism. We detail empirical studies through which the gluon and quark orbital angular momentum contributions, quark-flavor by quark-flavor, can be elucidated.
Date: August 23, 2006
Creator: Brodsky, S. J. & Gardner, S.
Object Type: Article
System: The UNT Digital Library
An indirect measurement of the width of the w boson at the D0 experiment (open access)

An indirect measurement of the width of the w boson at the D0 experiment

This thesis presents an indirect measurement of the width of the W boson using data collected at the D0 experiment, a multipurpose particle detector utilizing the Fermilab Tevatron. The W width was determined from the ratio of W {yields} {mu}{nu} to Z {yields} {mu}{sup +}{mu}{sup -} cross sections to be {Gamma}{sub W} = 2168 {+-} 22(stat) {+-} 62(syst){sub -16}{sup +24}(pdf) {+-} 4(other) MeV, in good agreement with the Standard Model prediction and other experimental measurements. In addition there is a description of how work made towards this measurement has been used to improve the parameterized detector simulation, a vital tool in the obtention of physics results from signals observed in the detector, and in estimating the uncertainty due to choice of PDF, which is of interest for all measurements made at hadron colliders.
Date: August 1, 2006
Creator: Telford, Paul
Object Type: Thesis or Dissertation
System: The UNT Digital Library
NSRL Energy Loss Calculator (open access)

NSRL Energy Loss Calculator

N/A
Date: August 1, 2006
Creator: B., Vankuik; Gardner, C.; Bellavia, S.; Rusek, A. & Brown, K.
Object Type: Report
System: The UNT Digital Library
Final Report on the Clean Energy/Air Quality Integration Initiative Pilot Project of the U.S. Department of Energy's Mid-Atlantic Regional Office (open access)

Final Report on the Clean Energy/Air Quality Integration Initiative Pilot Project of the U.S. Department of Energy's Mid-Atlantic Regional Office

The MARO pilot project represents the first effort in the country to seek to obtain credit under a Clean Air Act (CAA) State Implementation Plan (SIP) for nitrogen oxide (NOx) emission reductions.
Date: August 1, 2006
Creator: Jacobson, D.; O'Connor, P.; High, C. & Brown, J.
Object Type: Report
System: The UNT Digital Library
Metal enriched gaseous halos around distant radio galaxies: Clues to feedback in galaxy formation (open access)

Metal enriched gaseous halos around distant radio galaxies: Clues to feedback in galaxy formation

We present the results of an optical and near-IR spectroscopic study of giant nebular emission line halos associated with three z > 3 radio galaxies, 4C 41.17, 4C 60.07 and B2 0902+34. Previous deep narrow band Ly{alpha} imaging had revealed complex morphologies with sizes up to 100 kpc, possibly connected to outflows and AGN feedback from the central regions. The outer regions of these halos show quiet kinematics with typical velocity dispersions of a few hundred km s{sup -1}, and velocity shears that can mostly be interpreted as being due to rotation. The inner regions show shocked cocoons of gas closely associated with the radio lobes. These display disturbed kinematics and have expansion velocities and/or velocity dispersions >1000 km s{sup -1}. The core region is chemically evolved, and we also find spectroscopic evidence for the ejection of enriched material in 4C 41.17 up to a distance of {approx} 60 kpc along the radio-axis. The dynamical structures traced in the Ly{alpha} line are, in most cases, closely echoed in the Carbon and Oxygen lines. This shows that the Ly{alpha} line is produced in a highly clumped medium of small filling factor, and can therefore be used as a tracer of the …
Date: August 1, 2006
Creator: Reuland, M.; van Breugel, W.; de Vries, W.; Dopita, A.; Dey, A.; Miley, G. et al.
Object Type: Article
System: The UNT Digital Library
A Collection of Articles Reprinted from Science & Technology Review on University Relations Program (open access)

A Collection of Articles Reprinted from Science & Technology Review on University Relations Program

This month's issue has the following articles: (1) The Power of Partnership--Livermore researchers forge strategic collaborations with colleagues from other University of California campuses to further science and better protect the nation; (2) Collaborative Research Prepares Our Next-Generation Scientists and Engineers--Commentary by Laura R. Gilliom; (3) Next-Generation Scientists and Engineers Tap Lab's Resources--University of California Ph.D. candidates work with Livermore scientists and engineers to conduct fundamental research as part of their theses; (4) The Best and the Brightest Come to Livermore--The Lawrence Fellowship Program attracts the most sought-after postdoctoral researchers to the Laboratory; and (5) Faculty on Sabbatical Find a Good Home at Livermore--Faculty members from around the world come to the Laboratory as sabbatical scholars.
Date: August 23, 2006
Creator: Radousky, H; Rennie, G & Henke, A
Object Type: Report
System: The UNT Digital Library
New Developments in Measurements of CP Violation (open access)

New Developments in Measurements of CP Violation

We present several alternative techniques used by the BABAR Collaboration in order to measure the Unitarity Triangle angle {gamma}. We also present the results of two searches designed to improve the measurements of sin(2{beta}) using penguin B decay modes by reducing the hadronic corrections uncertainties.
Date: August 11, 2006
Creator: Benelli, Gabriele
Object Type: Article
System: The UNT Digital Library
Experimental discrimination between charge 2e/3 top quark and charge 4e/3 exotic quark production scenarios (open access)

Experimental discrimination between charge 2e/3 top quark and charge 4e/3 exotic quark production scenarios

None
Date: August 1, 2006
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 scalar bottom quarks in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for pair production of scalar bottom quarks in p anti-p collisions at s**(1/2) = 1.96-TeV

A search for direct production of scalar bottom quarks ({bar b}) is performed with 310 pb{sup -1} of data collected by the D0 experiment in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron Collider. The topology analyzed consists of two b jets and an imbalance in transverse momentum due to undetected neutralinos ({tilde {chi}}{sub 1}{sup 0}), with {tilde {chi}}{sub 1}{sup 0} assumed to be the lightest supersymmetric particle. They find the data consistent with standard model expectations, and set a 95% C.L. exclusion domain in the (m{sub {tilde b}}, m{sub {tilde {chi}}}) mass plane, improving significantly upon the results from Run I of the Tevatron.
Date: August 1, 2006
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 ratios of the Z/gamma* + >= n jet production cross sections to the total inclusive Z/gamma* cross section in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the ratios of the Z/gamma* + >= n jet production cross sections to the total inclusive Z/gamma* cross section in p anti-p collisions at s**(1/2) = 1.96-TeV

We present a study of events with Z bosons and jets produced at the Fermilab Tevatron Collider in p{bar p} collisions at a center of mass energy of 1.96 TeV. The data sample consists of nearly 14,000 Z/{gamma}* {yields} e{sup +}e{sup -} candidates corresponding to the integrated luminosity of 340 pb{sup -1} collected using the D0 detector. Ratios of the Z/{gamma}* + {ge} n jet cross sections to the total inclusive Z/{gamma}* cross section have been measured for n = 1 to 4 jet events. Our measurements are found to be in good agreement with a next-to-leading order QCD calculation and with a tree-level QCD prediction with parton shower simulation and hadronization.
Date: August 1, 2006
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
Surface-wave and refraction tomography at the FACT Site, Sandia National Laboratories, Albuquerque, New Mexico. (open access)

Surface-wave and refraction tomography at the FACT Site, Sandia National Laboratories, Albuquerque, New Mexico.

We present a technique that allows for the simultaneous acquisition and interpretation of both shear-wave and compressive-wave 3-D velocities. The technique requires no special seismic sources or array geometries, and is suited to studies with small source-receiver offsets. The method also effectively deals with unwanted seismic arrivals by using the statistical properties of the data itself to discriminate against spurious picks. We demonstrate the technique with a field experiment at the Facility for Analysis, Calibration, and Testing at Sandia National Laboratories, Albuquerque, New Mexico. The resulting 3-D shear-velocity and compressive-velocity distributions are consistent with surface geologic mapping. The averaged velocities and V{sub p}/V{sub s} ratio in the upper 30 meters are also consistent with examples found in the scientific literature.
Date: August 1, 2006
Creator: Abbott, Robert E.; Bartel, Lewis Clark; Pullammanappallil, Satish (Optim, Inc., Reno, NV) & Engler, Bruce Phillip
Object Type: Report
System: The UNT Digital Library
The intergalactic propagation of ultrahigh energy cosmic ray nuclei (open access)

The intergalactic propagation of ultrahigh energy cosmic ray nuclei

We investigate the propagation of ultra-high energy cosmic ray nuclei (A = 1-56) from cosmologically distant sources through the cosmic radiation backgrounds. Various models for the injected composition and spectrum and of the cosmic infrared background are studied using updated photodisintegration cross-sections. The observational data on the spectrum and the composition of ultra-high energy cosmic rays are jointly consistent with a model where all of the injected primary cosmic rays are iron nuclei (or a mixture of heavy and light nuclei).
Date: August 1, 2006
Creator: Hooper, Dan; Sarkar, Subir & Taylor, Andrew M.
Object Type: Article
System: The UNT Digital Library
Layered Materials as High Temperature Membranes in Hydrogen Production (open access)

Layered Materials as High Temperature Membranes in Hydrogen Production

None
Date: August 16, 2006
Creator: Sahimi, Muhammad & Tsotsis, Theodore T.
Object Type: Report
System: The UNT Digital Library
T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation (open access)

T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation

Characterization of stratigraphic sequences (T-R cycles or sequences) included outcrop studies, well log analysis and seismic reflection interpretation. These studies were performed by researchers at the University of Alabama, Wichita State University and McGill University. The outcrop, well log and seismic characterization studies were used to develop a depositional sequence model, a T-R cycle (sequence) model, and a sequence stratigraphy predictive model. The sequence stratigraphy predictive model developed in this study is based primarily on the modified T-R cycle (sequence) model. The T-R cycle (sequence) model using transgressive and regressive systems tracts and aggrading, backstepping, and infilling intervals or sections was found to be the most appropriate sequence stratigraphy model for the strata in the onshore interior salt basins of the Gulf of Mexico to improve petroleum stratigraphic trap and specific reservoir facies imaging, detection and delineation. The known petroleum reservoirs of the Mississippi Interior and North Louisiana Salt Basins were classified using T-R cycle (sequence) terminology. The transgressive backstepping reservoirs have been the most productive of oil, and the transgressive backstepping and regressive infilling reservoirs have been the most productive of gas. Exploration strategies were formulated using the sequence stratigraphy predictive model and the classification of the known petroleum …
Date: August 30, 2006
Creator: Mancini, Ernest A.
Object Type: Report
System: The UNT Digital Library
CHARACTERIZATION AND MONITORING OF NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUNDWATER: A SYSTEMS APPROACH (open access)

CHARACTERIZATION AND MONITORING OF NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUNDWATER: A SYSTEMS APPROACH

The objective of this document is to examine the use of a phased approach to characterizing and monitoring (C&M) natural attenuation processes and enhanced attenuation processes and to identify promising tools and techniques by which to accomplish the C&M. We will investigate developing techniques, such as molecular-based assessment tools, and existing tools that traditionally have not been used for monitoring the performance of environmental remediation technologies. Case studies will be used to provide examples of how non-traditional methods are being employed as characterization and monitoring tools to support MNA and EA. The document is not focused on a specific group of readers but rather is broadly directed with the intent that readers may gain information useful to their purposes. Thus, regulators may see some future characterization and monitoring techniques; end users may find novel ways to make MNA or EA more effective or efficient at their site; researchers may identify new areas for development or new and better combinations of existing methods. One consequence of this broad approach is that some readers may find certain sections either too rudimentary or too advanced for their needs. Hopefully, all will be able to use at least some of the document.
Date: August 10, 2006
Creator: Looney, B.; Michael Heitkamp, M.; Gary Wein (NOEMAIL), G.; Christopher Bagwell, C.; Karen Vangelas, K.; Karen-M Adams, K. et al.
Object Type: Report
System: The UNT Digital Library
The Efficient Windows Collaborative: Final Report (open access)

The Efficient Windows Collaborative: Final Report

The Efficient Windows Collaborative (EWC) is a coalition of manufacturers, component suppliers, government agencies, research institutions, and others who partner to expand the market for energy efficient window products. Funded through a cooperative agreement with the U.S. Department of Energy, the EWC provides education, communication and outreach in order to transform the residential window market to 70% energy efficient products by 2005. Implementation of the EWC is managed by the Alliance to Save Energy, with support from the University of Minnesota and Lawrence Berkeley National Laboratory.
Date: August 11, 2006
Creator: Alliance to Save Energy (U.S.)
Object Type: Report
System: The UNT Digital Library