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201 MHz Cavity R&D for MUCOOL and MICE (open access)

201 MHz Cavity R&D for MUCOOL and MICE

We describe the design, fabrication, analysis and preliminary testing of the prototype 201 MHz copper cavity for a muon ionization cooling channel. Cavity applications include the Muon Ionization Cooling Experiment (MICE) as well as cooling channels for a neutrino factory or a muon collider. This cavity was developed by the US muon cooling (MUCOOL) collaboration and is being tested in the MUCOOL Test Area (MTA) at Fermilab. To achieve a high accelerating gradient, the cavity beam irises are terminated by a pair of curved, thin beryllium windows. Several fabrication methods developed for the cavity and windows are novel and offer significant cost savings as compared to conventional construction methods. The cavity's thermal and structural performances are simulated with an FEA model. Preliminary high power RF commissioning results will be presented.
Date: June 23, 2006
Creator: Li, Derun; Virostek, Steve; Zisman, Michael; Norem, Jim; Bross,Alan; Moretti, Alfred et al.
Object Type: Article
System: The UNT Digital Library
Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling (open access)

Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling

Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, and economic projections. These data are available at various spatial and temporal scales, which may be different from those needed by the energy modeling community. If the translation from the original format to the format required by the energy researcher is incorrect, then resulting models can produce misleading conclusions. This is of increasing importance, because of the fine resolution data required by models for new alternative energy sources such as wind and distributed generation. This paper addresses the matter by applying spatial statistical techniques which improve the usefulness of spatial data sets (maps) that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) imputing missing data and (3) merging spatial data sets.
Date: June 23, 2006
Creator: Johanesson, G; Stewart, J S; Barr, C; Sabeff, L B; George, R; Heimiller, D et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 108, No. 72, Ed. 1 Friday, June 23, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 108, No. 72, Ed. 1 Friday, June 23, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 23, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
An Anti-Symmetric Lattice for High-Intensity Rapid Cycling Synchrotrons. (open access)

An Anti-Symmetric Lattice for High-Intensity Rapid Cycling Synchrotrons.

Rapid cycling synchrotrons (RCSs) are used in many high power facilities like spallation neutron sources and proton drivers to accumulate and accelerate proton beams. In such accelerators, beam collimation plays a crucial role in reducing the uncontrolled beam loss. Furthermore, injection and extraction sections often need to reside in dispersion-free regions to avoid couplings; sizeable drift space is needed to house the RF accelerating cavities; long, uninterrupted straights are desired to ease injection tuning and to raise collimation efficiency. Finally, the machine circumference needs to be small to reduce construction costs. In this paper, we present a lattice satisfying these needs. The lattice contains a drift created by a missing dipole near the peak dispersion to facilitate longitudinal collimation. The compact FODO arc allows easy orbit, tune, coupling, and chromatic correction. The doublets provide long uninterrupted straights. The four-fold lattice symmetry separates injection, extraction, and collimation to different straights. This lattice is adopted for the China Spallation Neutron Source (CSNS) synchrotron [1].
Date: June 23, 2006
Creator: Wei, J.; Wang, S.; Fang, S.-X.; Lee, Y. Y.; Machida, S.; Prior, C. et al.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 224, Ed. 1 Friday, June 23, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 224, Ed. 1 Friday, June 23, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 23, 2006
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam Pipe Desorption Rate in Rhic. (open access)

Beam Pipe Desorption Rate in Rhic.

In the past, an increase of beam intensity in RHIC has caused several decades of pressure rises in the warm sections during operation. This has been a major factor limiting the RHIC luminosity. About 430 meters of NEG coated beam pipes have been installed in the warm sections to ameliorate this problem. Beam ion induced desorption is one possible cause of pressure rises. A series beam studies in RHIC has been dedicated to estimate the desorption rate of various beam pipes (regular and NEG coated) at various warm sections. Correctors were used to generate local beam losses and consequently local pressure rises. The experimental results are presented and analyzed in this paper.
Date: June 23, 2006
Creator: Huang, H.; Fischer, W.; He, P.; Hseuh, H. C.; Iriso, U.; Ptitsyn, V. et al.
Object Type: Article
System: The UNT Digital Library
Boerne Star & Recorder (Boerne, Tex.), Vol. 100, No. 50, Ed. 1 Friday, June 23, 2006 (open access)

Boerne Star & Recorder (Boerne, Tex.), Vol. 100, No. 50, Ed. 1 Friday, June 23, 2006

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: June 23, 2006
Creator: Cartwright, Brian
Object Type: Newspaper
System: The Portal to Texas History
Cancellation of spin and orbital magnetic moments in (delta)-Pu: theory (open access)

Cancellation of spin and orbital magnetic moments in (delta)-Pu: theory

Density functional theory (DFT), in conjunction with the fixed-spin-moment (FSM) method, spin-orbit coupling (SO), and orbital polarization (OP), is shown to retain key features of the conventional DFT treatment of {delta}-Pu while at the same time not producing the substantial net magnetic moments commonly predicted by this theory. It is shown that when a small adjustment of the spin moment (less than 20%) is allowed, a complete spin- and orbital-moment cancellation occurs which results in a zero net magnetic moment in {delta}-Pu. This minor modification, accomplished by the FSM method, is shown to have a very small effect on the calculated total energy as well as the electron density-of-states (DOS). The photoemission spectra (PES), obtained from the DOS of the present model, compares equal or better to measured spectra, than that of two other recent non-magnetic models for {delta}-Pu.
Date: June 23, 2006
Creator: Soderlind, P
Object Type: Article
System: The UNT Digital Library
The Challenges to Coupling Dynamic Geospatial Models (open access)

The Challenges to Coupling Dynamic Geospatial Models

Many applications of modeling spatial dynamic systems focus on a single system and a single process, ignoring the geographic and systemic context of the processes being modeled. A solution to this problem is the coupled modeling of spatial dynamic systems. Coupled modeling is challenging for both technical reasons, as well as conceptual reasons. This paper explores the benefits and challenges to coupling or linking spatial dynamic models, from loose coupling, where information transfer between models is done by hand, to tight coupling, where two (or more) models are merged as one. To illustrate the challenges, a coupled model of Urbanization and Wildfire Risk is presented. This model, called Vesta, was applied to the Santa Barbara, California region (using real geospatial data), where Urbanization and Wildfires occur and recur, respectively. The preliminary results of the model coupling illustrate that coupled modeling can lead to insight into the consequences of processes acting on their own.
Date: June 23, 2006
Creator: Goldstein, N
Object Type: Article
System: The UNT Digital Library
Changing Postal ZIP Code Boundaries (open access)

Changing Postal ZIP Code Boundaries

This report discusses the changing of ZIP Code system and the implications of such an action. The process places responsibility on district managers, rather than local postmasters, to review requests for boundary adjustment, to evaluate costs and benefits of alternative solutions to identified problems, and to provide a decision within 60 days.
Date: June 23, 2006
Creator: Stevens, Nye
Object Type: Report
System: The UNT Digital Library
CHARACTERIZATION OF DAMAGED MATERIALS (open access)

CHARACTERIZATION OF DAMAGED MATERIALS

Thermal damage experiments were conducted on LX-04, LX-10, and LX-17 at high temperatures. Both pristine and damaged samples were characterized for their material properties. A pycnometer was used to determine sample true density and porosity. Gas permeability was measured in a newly procured system (diffusion permeameter). Burn rate was measured in the LLNL strand burner. Weight losses upon thermal exposure were insignificant. Damaged pressed parts expanded, resulting in a reduction of bulk density by up to 10%. Both gas permeabilities and burn rates of the damaged samples increased by several orders of magnitude due to higher porosity and lower density. Moduli of the damaged materials decreased significantly, an indication that the materials became weaker mechanically. Damaged materials were more sensitive to shock initiation at high temperatures. No significant sensitization was observed when the damaged samples were tested at room temperature.
Date: June 23, 2006
Creator: Hsu, P C; Dehaven, M; McClelland, M; Chidester, S & Maienschein, J L
Object Type: Article
System: The UNT Digital Library
Choice of Proton Driver Parameters for a Neutrino Factory. (open access)

Choice of Proton Driver Parameters for a Neutrino Factory.

We discuss criteria for designing an optimal ''green field'' proton driver for a neutrino factory. The driver parameters are determined by considerations of space charge, power capabilities of the target, beam loading and available RF peak power.
Date: June 23, 2006
Creator: Kirk, H. G.; Berg, J. S.; Fernow, R. C.; Gallardo, J. C.; Simos, N. & Weng, W.
Object Type: Article
System: The UNT Digital Library
Clean Air Act: EPA Should Improve the Management of Its Air Toxics Program (open access)

Clean Air Act: EPA Should Improve the Management of Its Air Toxics Program

A letter report issued by the Government Accountability Office with an abstract that begins "The Environmental Protection Agency's (EPA) most recent data indicate that 95 percent of all Americans face an increased likelihood of developing cancer as a result of breathing air toxics--pollutants such as benzene and asbestos that may cause cancer or other serious health problems. Sources of air toxics include large industrial facilities, smaller facilities such as dry cleaners, and cars and trucks. The 1990 Clean Air Act Amendments required EPA to regulate 190 pollutants from these sources through a multifaceted regulatory program. While EPA issues federal standards, state and local agencies generally administer these standards, and some develop their own rules to complement the federal standards. In this context, GAO was asked to assess (1) EPA's progress and challenges in implementing the air toxics program, (2) available information on the program's costs and benefits, and (3) practices of state and local air toxics programs."
Date: June 23, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 111, No. 25, Ed. 1 Friday, June 23, 2006 (open access)

The Clifton Record (Clifton, Tex.), Vol. 111, No. 25, Ed. 1 Friday, June 23, 2006

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: June 23, 2006
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
Coal Mine Safety (open access)

Coal Mine Safety

This report reviews the safety and health record of the mining industry, describes the regulatory regime, and analyzes current legislative and regulatory initiatives.
Date: June 23, 2006
Creator: Rappaport, Edward
Object Type: Report
System: The UNT Digital Library
Coast Guard: Status of Deepwater Fast Response Cutter Design Efforts (open access)

Coast Guard: Status of Deepwater Fast Response Cutter Design Efforts

A letter report issued by the Government Accountability Office with an abstract that begins "The Coast Guard has been pursing a replacement vessel for its aging and deteriorating patrol boats as part of the Integrated Deepwater System (or Deepwater) acquisition. Originally, all 49 of the Coast Guard's 110-foot patrol boats were to be converted into 123-foot patrol boats as a bridging strategy until a replacement vessel, the 140-foot Fast Response Cutter (FRC) came on line beginning in 2018. The initial conversions of the 110-foot patrol boats proved unsuccessful, though, and this prompted the Coast Guard to cancel further patrol boat conversions and accelerate the design and delivery of the FRC from 2018 to 2007. Early design efforts called for the FRC's hull, decks, and bulkheads to be made from composite materials rather than steel. Recently, design problems with the FRC's hull shape and weight have raised questions about the viability of the FRC design and use of composite materials. This report examines (1) the factors that went into the decision to use composite materials for the FRC hull, (2) the types of composite materials that have been selected for the FRC hull, (3) the extent of contingency plans developed for …
Date: June 23, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Combined Phase SpaceCharacterization at the PEP-II IP using Single-beam and Luminous-region Measurements (open access)

Combined Phase SpaceCharacterization at the PEP-II IP using Single-beam and Luminous-region Measurements

We present a novel method to characterize the e{sup {+-}} phase space at the IP of the SLAC B-factory, that combines single-beam measurements with a detailed mapping of luminous-region observables. Transverse spot sizes are determined in the two rings with synchrotron-light monitors and extrapolated to the IP using measured lattice functions. The specific luminosity, which is proportional to the inverse product of the overlap IP beam sizes, is continuously monitored using radiative/Bhabha events. The spatial variation of the luminosity and of the transverse-boost distribution of the colliding e{sup {+-}}, are measured using e{sup +}e{sup -} {yields} {mu}{sup +}{mu}{sup -} events reconstructed in the BABAR detector. The combination of these measurements provide constraints on the emittances, horizontal and vertical spot sizes, angular divergences and {beta} functions of both beams at the IP during physics data-taking. Preliminary results of this combined spot-size analysis are confronted with independent measurements of IP {beta}-functions and overlap IP beam sizes at low beam current.
Date: June 23, 2006
Creator: Bevan, A.; /Queen Mary, U. of London; Kozanecki, W.; /Saclay; Viaud, B.; U., /Montreal et al.
Object Type: Article
System: The UNT Digital Library
COMMENT ON THE HEALY'S SYMPLECTIFICATION ALGORITHM. (open access)

COMMENT ON THE HEALY'S SYMPLECTIFICATION ALGORITHM.

For long-term tracking, it is important to have symplectic maps for the various electromagnetic elements in an accelerator ring. While many standard elements are handled well by modern tracking programs, new magnet configurations (e.g., a helical dipole with a superimposed solenoid [1]) are being used in real accelerators. Transport matrices and higher terms may be calculated by numerical integration through model-generated or measured field maps. The resulting matrices are most likely not quite symplectic due to numerical errors in the integrators as well as the fieldmaps. In his thesis [2], Healy presented a simple algorithm to symplectify a matrix. While the method is quite robust, this paper presents a discussion of its limitations.
Date: June 23, 2006
Creator: MacKay, W. W.
Object Type: Article
System: The UNT Digital Library
Comparison of Packed Beds and Qiagen Columns for Recovering Trace Amounts of B. anthracis DNA from Liquid Suspensions (open access)

Comparison of Packed Beds and Qiagen Columns for Recovering Trace Amounts of B. anthracis DNA from Liquid Suspensions

The goal of this work was to optimize and evaluate LLNL's in-bed amplification technology to improve the level of detection for suspensions containing trace amounts of anthracis DNA. The binding/cleaning performance of the packed bed is compared to the conventional commercial approach; Qiagen column cleanup and elution, followed by detection through an ex-situ amplification process. Five liquid suspensions were spiked with B.anthracis DNA in concentration series. These suspensions were: (1) water, (2) water with EDTA, (3) dirty water from carpet extraction, (4) dirty carpet extraction with phosphate buffered saline (PBS) plus 0.1% Tween 20 plus 0.1% gelatin, and (5) a subway aerosol collected in water. Each suspension matrix was spiked with DNA and injected (in replicate) into either Qiagen Microcolumns (using the kit processing instructions) or LLNL's packed bed (using the LLNL in-bed purification and amplification protocol). The process output was assayed by quantitative polymerase chain reaction (QPCR). Table ES-1 shows the level of DNA (pg per 100 uL of input suspension) that resulted in successful amplification for all reactions (X=Y), and the level for which at least one of the reactions was successful (X>0). For each suspension and DNA concentration, there were Y QPCR assays of which X showed …
Date: June 23, 2006
Creator: Sorensen, K; Arroyo, E; Erler, A; Christian, A T; Camp, D & Wheeler, E K
Object Type: Report
System: The UNT Digital Library
Coupled Multi-Electrode Investigation of Crevice Corrosion of AISI 316 Stainless Steel (open access)

Coupled Multi-Electrode Investigation of Crevice Corrosion of AISI 316 Stainless Steel

Close packed coupled multi-electrodes arrays (MEA) simulating a planar electrode were used to measure the current evolution as a function of position during initiation and propagation of crevice corrosion of AISI 316 stainless steel. Scaling laws derived from polarization data enabled the use of rescaled crevices providing spatial resolution. Crevice corrosion of AISI 316 stainless steel in 0.6 M NaCl at 50 C was found to initiate close to the crevice mouth and to spread inwards with time. The local crevice current density increased dramatically over a short period to reach a limiting value.
Date: June 23, 2006
Creator: Bocher, Florent; Presuel-Moreno, Francisco; Budinasky, Noah D. & Scully, John R.
Object Type: Report
System: The UNT Digital Library
CRYSTALLINE BEAMS AT HIGH ENERGIES. (open access)

CRYSTALLINE BEAMS AT HIGH ENERGIES.

Previously it was shown that by crystallizing each of the two counter-circulating beams, a much larger beam-beam tune shift can be tolerated during the beam-beam collisions; thus a higher luminosity can be reached for colliding beams [1]. On the other hand, crystalline beams can only be formed at energies below the transition energy ({gamma}{sub T}) of the accelerators [2]. In this paper, we investigate the formation of crystals in a high-{gamma}{sub T} lattice that also satisfies the maintenance condition for a crystalline beam [3].
Date: June 23, 2006
Creator: WEI, J.; OKAMOTO, H.; YURI, Y.; SESSLER, A. & MACHIDA, S.
Object Type: Article
System: The UNT Digital Library
Cuba: Issues for the 109th Congress (open access)

Cuba: Issues for the 109th Congress

This report discusses U.S.-Cuba relations since the early 1960s. There are several schools of thought on how to achieve the objective of bringing democracy and respect for human rights to Cuba: some advocate maximum pressure on Cuba until reforms are enacted; others argue for lifting some U.S. sanctions judged to be hurting the Cuban people; and still others call for a swift normalization of U.S.-Cuban relations.
Date: June 23, 2006
Creator: Sullivan, Mark P.
Object Type: Report
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 23, No. 06, Ed. 1 Friday, June 23, 2006 (open access)

Dallas Voice (Dallas, Tex.), Vol. 23, No. 06, Ed. 1 Friday, June 23, 2006

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: June 23, 2006
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
DETONATION PRESSURE MEASUREMENTS ON PETN (open access)

DETONATION PRESSURE MEASUREMENTS ON PETN

PETN is widely recognized as an example of nearly ideal detonation performance. The chemical composition is such that little or no carbon is produced in the detonation products. The reaction zone width is less than currently detectable. (<1 ns) Observations on PETN have thus become a baseline for EOS model predictions. It has therefore become important to characterize the detonation parameters as accurately as possible in order to provide the most exacting comparisons of EOS predictions with experimental results. We undertook a painstaking review of the detonation pressure measurements reported in an earlier work that was presented at the Fifth Detonation Symposium and found that corrections were required in determining the shock velocity in the PMMA witness material. We also refined the impedance calculation to account for the difference between the usual ''acoustic'' method and the more accurate Riemann integral. Our review indicates that the CJ pressures previously reported for full density PETN require an average lowering of about 6 percent. The lower densities require progressively smaller corrections. We present analysis of the records, supporting hydrodynamic simulations, the Riemann integral results, and EOS parameter values derived from the revised results.
Date: June 23, 2006
Creator: Green, L. G. & Lee, E. L.
Object Type: Article
System: The UNT Digital Library