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A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT (open access)

A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT

We have achieved {approx}30 psec single-photoelectron and {approx}12ps for multi-photoelectron timing resolution with a new 64 pixel Burle MCP-PMT with 10 micron microchannel holes. We have also demonstrated that this detector works in a magnetic field of 15kG, and achieved a single-photoelectron timing resolution of better than 60 psec. The study is relevant for a new focusing DIRC RICH detector for particle identification at future Colliders such as the super B-factory or ILC, and for future TOF techniques. This study shows that a highly pixilated MCP-PMT can deliver excellent timing resolution.
Date: July 5, 2006
Creator: Va'vra, J.; Benitez, J.; Coleman, J.; Leith, D. W. G. S.; Mazaheri, G.; Ratcliff, B. et al.
Object Type: Article
System: The UNT Digital Library
All One-loop Maximally Helicity Violating Gluonic Amplitudes in QCD (open access)

All One-loop Maximally Helicity Violating Gluonic Amplitudes in QCD

We use on-shell recursion relations to compute analytically the one-loop corrections to maximally-helicity-violating n-gluon amplitudes in QCD. The cut-containing parts have been computed previously; our work supplies the remaining rational parts for these amplitudes, which contain two gluons of negative helicity and the rest positive, in an arbitrary color ordering. We also present formulae specific to the six-gluon cases, with helicities (-+-+++) and (-++-++), as well as numerical results for six, seven, and eight gluons. Our construction of the n-gluon amplitudes illustrates the relatively modest growth in complexity of the on-shell-recursive calculation as the number of external legs increases. These amplitudes add to the growing body of one-loop amplitudes known for all n, which are useful for studies of general properties of amplitudes, including their twistor-space structure.
Date: July 5, 2006
Creator: Berger, Carola F.; Bern, Zvi; Dixon, Lance J.; Forde, Darren & Kosower, David A.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 108, No. 82, Ed. 1 Wednesday, July 5, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 108, No. 82, Ed. 1 Wednesday, July 5, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 5, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Application of a New Method for Analyzing Images: Two-Dimensional Non-Linear Additive Decomposition (open access)

Application of a New Method for Analyzing Images: Two-Dimensional Non-Linear Additive Decomposition

This paper documents the application of a new image processing algorithm, two-dimensional non-linear additive decomposition (NLAD), which is used to identify regions in a digital image whose gray-scale (or color) intensity is different than the surrounding background. Standard image segmentation algorithms exist that allow users to segment images based on gray-scale intensity and/or shape. However, these processing techniques do not adequately account for the image noise and lighting variation that typically occurs across an image. NLAD is designed to separate image noise and background from artifacts thereby providing the ability to consistently evaluate images. The decomposition techniques used in this algorithm are based on the concepts of mathematical morphology. NLAD emulates the human capability of visually separating an image into different levels of resolution components, denoted as ''coarse'', ''fine'', and ''intermediate''. Very little resolution information overlaps any two of the component images. This method can easily determine and/or remove trends and noise from an image. NLAD has several additional advantages over conventional image processing algorithms, including no need for a transformation from one space to another, such as is done with Fourier transforms, and since only finite summations are required, the calculational effort is neither extensive nor complicated.
Date: July 5, 2006
Creator: Zaccaria, M. A.; Drudnoy, D. M. & Stasenko, J. E.
Object Type: Article
System: The UNT Digital Library
Army Officer Shortages: Background and Issues for Congress (open access)

Army Officer Shortages: Background and Issues for Congress

This report assesses the extent of the Army officer shortfall, examines perceived causes, reviews recent retention initiatives, identifies other possible retention incentives, and concludes with a review of possible options for Congress. This report is focused on the Army’s “line” or basic branch officers.
Date: July 5, 2006
Creator: Henning, Charles A.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 236, Ed. 1 Wednesday, July 5, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 236, Ed. 1 Wednesday, July 5, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 5, 2006
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Biomolecular Origin of The Rate-Dependent Deformation of Prismatic Enamel (open access)

Biomolecular Origin of The Rate-Dependent Deformation of Prismatic Enamel

Penetration deformation of columnar prismatic enamel was investigated using instrumented nanoindentation testing, carried out at three constant strain rates (0.05 s{sup -1}, 0.005 s{sup -1}, and 0.0005 s{sup -1}). Enamel demonstrated better resistance to penetration deformation and greater elastic modulus values were measured at higher strain rates. The origin of the rate-dependent deformation was rationalized to be the shear deformation of nanoscale protein matrix surrounding each hydroxyapatite crystal rods. And the shear modulus of protein matrix was shown to depend on strain rate in a format: G{sub p} = 0.213 + 0.021 ln {dot {var_epsilon}}. Most biological composites compromise reinforcement mineral components and an organic matrix. They are generally partitioned into multi-level to form hierarchical structures that have supreme resistance to crack growth [1]. The molecular mechanistic origin of toughness is associated with the 'sacrificial chains' between the individual sub-domains in a protein molecule [2]. As the protein molecule is stretched, these 'sacrificial chains' break to protect its backbone and dissipate energy [3]. Such fresh insights are providing new momentum toward updating our understanding of biological materials [4]. Prismatic enamel in teeth is one such material. Prismatic microstructure is frequently observed in the surface layers of many biological materials, as …
Date: July 5, 2006
Creator: Zhou, J & Hsiung, L
Object Type: Article
System: The UNT Digital Library
Border Security: Investigators Transported Radioactive Sources Across Our Nation's Borders at Two Locations (open access)

Border Security: Investigators Transported Radioactive Sources Across Our Nation's Borders at Two Locations

Testimony issued by the Government Accountability Office with an abstract that begins "Given today's unprecedented terrorism threat environment and the resulting widespread congressional and public interest in the security of our nation's borders, GAO conducted an investigation testing whether radioactive sources could be smuggled across U.S. borders. Most travelers enter the United States through the nation's 154 land border ports of entry. Department of Homeland Security U.S. Customs and Border Protection (CBP) inspectors at ports of entry are responsible for the primary inspection of travelers to determine their admissibility into the United States and to enforce laws related to preventing the entry of contraband, such as drugs and weapons of mass destruction. GAO's testimony provides the results of undercover tests made by its investigators to determine whether monitors at U.S. ports of entry detect radioactive sources in vehicles attempting to enter the United States. GAO also provides observations regarding the procedures that CBP inspectors followed during its investigation. GAO has also issued a report on the results of this investigation (GAO-06-545R)."
Date: July 5, 2006
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
The Capitol Visitor Center: An Overview (open access)

The Capitol Visitor Center: An Overview

On June 20, 2000, congressional leaders of both parties gathered to participate in a symbolic groundbreaking ceremony for the Capitol Visitor Center (CVC). The center has been designed to enhance the security, educational experience, and comfort of those visiting the U.S. Capitol when it is completed. The cost of the center is estimated to be at least $555 million. This report details the different methods of funding for the center, as well as the design and development process for the center.
Date: July 5, 2006
Creator: Stathis, Stephen W.
Object Type: Report
System: The UNT Digital Library
The Capitol Visitor Center: An Overview (open access)

The Capitol Visitor Center: An Overview

This report presents the cost of the center, the most extensive addition to the Capitol since the Civil War, and the largest in the structure’s more than 200-year history, is now estimated to be at least $555 million. The project is being financed with appropriated funds, and a total of $65 million from private donations and revenue generated by the sale of commemorative coins.
Date: July 5, 2006
Creator: Stathis, Stephen W.
Object Type: Report
System: The UNT Digital Library
The Capitol Visitor Center: An Overview (open access)

The Capitol Visitor Center: An Overview

This report presents the cost of the center, the most extensive addition to the Capitol since the Civil War, and the largest in the structure’s more than 200-year history, is now estimated to be at least $555 million. The project is being financed with appropriated funds, and a total of $65 million from private donations and revenue generated by the sale of commemorative coins.
Date: July 5, 2006
Creator: Stathis, Stephen W.
Object Type: Report
System: The UNT Digital Library
Charm Mixing at BaBar (open access)

Charm Mixing at BaBar

We report on searches for D{sup 0}-{bar D}{sup 0} mixing using decay-time distributions of D{sup 0} {yields} K{pi} and D{sup 0} {yields} K{sup (*)}e{nu} decays and a lifetime ratio analysis of D{sup 0} {yields} K{sup +}K{sup -}, {pi}{sup +}{pi}{sup -} decays using 91 fb{sup -1} of e{sup +}e{sup -} data taken at the PEP-II asymmetric-energy storage ring at energies near 10.6 GeV. Searches for CP-violation in D{sup 0} mixing and decay are also reported, as well as a measurement of R{sub D}, the ratio of the doubly Cabibbo-suppressed decay rate to the Cabibbo-allowed decay rate.
Date: July 5, 2006
Creator: Cowan, Ray F.
Object Type: Article
System: The UNT Digital Library
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 20, Ed. 1 Wednesday, July 5, 2006 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 20, Ed. 1 Wednesday, July 5, 2006

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: July 5, 2006
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
The Colony Courier-Leader (The Colony, Tex.), Vol. 25, No. 22, Ed. 1 Wednesday, July 5, 2006 (open access)

The Colony Courier-Leader (The Colony, Tex.), Vol. 25, No. 22, Ed. 1 Wednesday, July 5, 2006

Weekly newspaper from The Colony, Texas that includes local, state, and national news along with advertising.
Date: July 5, 2006
Creator: Crimmins, Blaine
Object Type: Newspaper
System: The Portal to Texas History
Control of Surface Functional Groups on Pertechntate Sorption on Activated Carbon (open access)

Control of Surface Functional Groups on Pertechntate Sorption on Activated Carbon

{sup 99}Tc is highly soluble and poorly adsorbed by natural materials under oxidizing conditions, thus being of particular concern for radioactive waste disposal. Activated carbon can potentially be used as an adsorbent for removing Tc from aqueous solutions. We have tested six commercial activated carbon materials for their capabilities for sorption of pertechnetate (TcO{sub 4}{sup -}). The tested materials can be grouped into two distinct types: Type I materials have high sorption capabilities with the distribution coefficients (K{sub d}) varying from 9.5 x 10{sup 5} to 3.2 x 10{sup 3} mL/g as the pH changes from 4.5 to 9.5, whereas type II materials have relatively low sorption capabilities with K{sub d} remaining more or less constant (1.1 x 10{sup 3} - 1.8 x 10{sup 3} mL/g) over a similar pH range. The difference in sorption behavior between the two types of materials is attributed to the distribution of surface functional groups. The predominant surface groups are identified to be carboxylic and phenolic groups. The carboxylic group can be further divided into three subgroups A, B, and C in the order of increasing acidity. The high sorption capabilities of type I materials are found to be caused by the presence of …
Date: July 5, 2006
Creator: Wang, Y.; Gao, H.; Yeredla, R.; Xu, H.; Abrecht, M. & Stasio, G.D.
Object Type: Article
System: The UNT Digital Library
Deposit Summary (open access)

Deposit Summary

Deposit summary of $20.00 made on July 5, 2006.
Date: July 5, 2006
Creator: unknown
Object Type: Text
System: The UNT Digital Library
The Effect of Temperature on the Breakdown and Repassivation Potentials of Welded Alloy 22 In 5 M CACI2 (open access)

The Effect of Temperature on the Breakdown and Repassivation Potentials of Welded Alloy 22 In 5 M CACI2

The study of the electrochemical behavior of wrought and welded Alloy 22 was carried out in 5 M CaCl{sub 2} as a function of temperatures between 45 and 120 C with Multiple Crevice Assembly (MCA) specimens. The susceptibility to corrosion was found to increase with increase in electrolyte temperature in both the wrought (in the mill annealed condition) and the welded forms of the alloy. The weld metal was found to be less susceptible to localized corrosion under the conditions tested.
Date: July 5, 2006
Creator: IIevbare, G.O.
Object Type: Report
System: The UNT Digital Library

Ensemble: 2006-07-05 – Chamber Music Class

Access: Use of this item is restricted to the UNT Community
Chamber recital performed at the UNT College of Music Recital Hall
Date: July 5, 2006
Creator: University of North Texas. Chamber Music Class.
Object Type: Sound
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, July 5, 2006 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, July 5, 2006

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 5, 2006
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
FastBit -- Helps Finding the Proverbial Needle in a Haystack (open access)

FastBit -- Helps Finding the Proverbial Needle in a Haystack

FastBit is a software package designed to meet the searching and filtering needs of data intensive sciences. In these applications, scientists are trying to find nuggets of information from petabytes of raw data. FastBit has been demonstrated to be an order of magnitude faster than comparable technologies. In this brief report, we highlight how we work with a visualization team, a network security team and a DNA sequencing center to find the nuggets in their data.
Date: July 5, 2006
Creator: Wu, Kesheng "John"; Stockinger, Kurt; Shoshani, Arie & Wes, Bethel
Object Type: Report
System: The UNT Digital Library
Final Technical Report - In-line Uranium Immunosensor (open access)

Final Technical Report - In-line Uranium Immunosensor

In this project, personnel at Tulane University and Sapidyne Instruments Inc. developed an in-line uranium immunosensor that could be used to determine the efficacy of specific in situ biostimulation approaches. This sensor was designed to operate autonomously over relatively long periods of time (2-10 days) and was able to provide near real-time data about uranium immobilization in the absence of personnel at the site of the biostimulation experiments. An alpha prototype of the in-line immmunosensor was delivered from Sapidyne Instruments to Tulane University in December of 2002 and a beta prototype was delivered in November of 2003. The beta prototype of this instrument (now available commercially from Sapidyne Instruments) was programmed to autonomously dilute standard uranium to final concentrations of 2.5 to 100 nM (0.6 to 24 ppb) in buffer containing a fluorescently labeled anti-uranium antibody and the uranium chelator, 2,9-dicarboxyl-1,10-phenanthroline. The assay limit of detection for hexavalent uranium was 5.8 nM or 1.38 ppb. This limit of detection is well below the drinking water standard of 30 ppb recently promulgated by the EPA. The assay showed excellent precision; the coefficients of variation (CV’s) in the linear range of the assay were less than 5% and CV’s never rose above …
Date: July 5, 2006
Creator: Blake, Diane A.
Object Type: Report
System: The UNT Digital Library
Fish and Wildlife Service: Federal Assistance Program Is Making Progress in Addressing Previously Identified Concerns (open access)

Fish and Wildlife Service: Federal Assistance Program Is Making Progress in Addressing Previously Identified Concerns

Correspondence issued by the Government Accountability Office with an abstract that begins "The U.S. Fish and Wildlife Service (Service), within the Department of the Interior, uses tax receipts from the sale of certain hunting, fishing, and boating equipment to fund the Wildlife and Sport Fish Restoration programs, which provide grants to state fish and wildlife management agencies to restore, conserve, manage, and enhance wildlife and sport fish resources. The Wildlife Restoration Program was established in 1938 following the passage of the Federal Aid in Wildlife Restoration Act, now referred to as the Pittman-Robertson Wildlife Restoration Act. The Sport Fish Restoration Program was established in 1950 by the Dingell-Johnson Sport Fish Restoration Act. Since their inception, according to the Service, these programs have provided more than $9.5 billion in grants to states and U.S. territories through fiscal year 2005. In 1999 and 2000, GAO identified several instances of mismanagement in these grant programs. Following GAO's work, Congress and the Service acted to improve the programs. In 1999 and 2000, GAO testified on the Service's management and oversight of funds used to administer the Wildlife and the Sport Fish Restoration programs. These testimonies identified several instances of mismanagement of administrative funds. For …
Date: July 5, 2006
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Gas Centrifuge Enrichment Plant Safeguards System Modeling (open access)

Gas Centrifuge Enrichment Plant Safeguards System Modeling

None
Date: July 5, 2006
Creator: Elayat, H A; O'Connell, W J & Boyer, B D
Object Type: Article
System: The UNT Digital Library
The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 1, Ed. 1 Wednesday, July 5, 2006 (open access)

The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 1, Ed. 1 Wednesday, July 5, 2006

Weekly newspaper from Goldthwaite, Texas that includes local, state, and national news along with extensive advertising.
Date: July 5, 2006
Creator: Bridges, Steven W.
Object Type: Newspaper
System: The Portal to Texas History