Considerations of bunch-spacing options for multi-bunch operation of the Tevatron Collider (open access)

Considerations of bunch-spacing options for multi-bunch operation of the Tevatron Collider

This discussion will consider a number of points relevant to limitations, advantages and disadvantages of various arrangements of bunches in the Tevatron proton-antiproton collider. The considerations discussed here will be limited to: (a) bunch spacing symmetry and relation to the relative luminosity at B0 and D0 and the beam-beam interaction with separated beams; (b) bunch spacing constraints imposed by Main Ring RF coalescing and the optics of beam separation at B0 and D0; and (c) bunch spacing constraints imposed by injection and abort kicker timing requirements, and by the Antiproton Source RF unstacking process. 20 figs., 17 tabs.
Date: December 14, 1989
Creator: Dugan, G.
Object Type: Report
System: The UNT Digital Library
Reactor containment analysis for BWR suppression systems. Progress report, April--October 1977 (open access)

Reactor containment analysis for BWR suppression systems. Progress report, April--October 1977

Work during the period included analytic studies of vent clearing and jet-slug dynamics and computer simulations (HEMP and CHAMP codes) of pressure suppression experiments.
Date: December 14, 1977
Creator: Edwards, L.L.
Object Type: Report
System: The UNT Digital Library
An Integral Design Technique for Wideband Multistage Transistor Amplifiers (open access)

An Integral Design Technique for Wideband Multistage Transistor Amplifiers

A philosophy for designing wideband multistage transistor amplifiers is presented. The amplifier was visualized as an integral unit, the interstage networks constituting the elements of the amplifier unit. By designing the amplifier as a unit and adjusting the over-all response (gain and bandwidth) with the interstage time constants, an increase in gain-bandwidth product was realized over the iteratively designed amplifiers. The resulting increase in gainbandwidth product resulted from absence of the bandwidth shrinkage factor for multistage amplifiers. Formulas were derived for both a two- and three- transistor integrally designed wideband amplifier, in which shunt peaking networks were used for coupling. Experimental amplifiers were con structcd following these formulas, and the observed performance agreed quite well with the calculations. (auth)
Date: December 14, 1961
Creator: Scott, L.
Object Type: Report
System: The UNT Digital Library
Kilowatt Isotope Power System: component test report for the ground demonstration system alternator stator. 78-KIPS-17 (open access)

Kilowatt Isotope Power System: component test report for the ground demonstration system alternator stator. 78-KIPS-17

The purpose of this test was to demonstrate that the alternator stator has satisfactorily completed sufficient testing to safisfy the requirements set forth within the Kilowatt Isotope Power System (KIPS) Component Test Specification for the GDS Alternator Stator (TS 2538). The results of the acceptance tests conducted on the alternator stator, S/N 003, are presented, and show that the stator did meet specified requirements.
Date: December 14, 1977
Creator: unknown
Object Type: Report
System: The UNT Digital Library
MACRO1: a code to test a methodology for analyzing nuclear-waste management systems (open access)

MACRO1: a code to test a methodology for analyzing nuclear-waste management systems

The code is primarily a manager of probabilistic data and deterministic mathematical models. The user determines the desired aggregation of the available models into a composite model of a physical system. MACRO1 then propagates the finite probability distributions of the inputs to the model to finite probability distributions over the outputs. MACRO1 has been applied to a sample analysis of a nuclear-waste repository, and its results compared satisfactorily with previously obtained Monte Carlo statistics.
Date: December 14, 1979
Creator: Edwards, L.L.
Object Type: Report
System: The UNT Digital Library
A Probabilistic Approach to Classifying Supernovae UsingPhotometric Information (open access)

A Probabilistic Approach to Classifying Supernovae UsingPhotometric Information

This paper presents a novel method for determining the probability that a supernova candidate belongs to a known supernova type (such as Ia, Ibc, IIL, etc.), using its photometric information alone. It is validated with Monte Carlo, and both space- and ground-based data. We examine the application of the method to well-sampled as well as poorly sampled supernova light curves and investigate to what extent the best currently available supernova models can be used for typing supernova candidates. Central to the method is the assumption that a supernova candidate belongs to a group of objects that can be modeled; we therefore discuss possible ways of removing anomalous or less well understood events from the sample. This method is particularly advantageous for analyses where the purity of the supernova sample is of the essence, or for those where it is important to know the number of the supernova candidates of a certain type (e.g., in supernova rate studies).
Date: December 14, 2006
Creator: Kuznetsova, Natalia V. & Connolly, Brian M.
Object Type: Article
System: The UNT Digital Library
ILC Reference Design Report: Accelerator Executive Summary (open access)

ILC Reference Design Report: Accelerator Executive Summary

The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radiofrequency (SCRF) accelerating cavities. The use of the SCRF technology was recommended by the International Technology Recommendation Panel (ITRP) in August 2004 [1], and shortly thereafter endorsed by the International Committee for Future Accelerators (ICFA). In an unprecedented milestone in high-energy physics, the many institutes around the world involved in linear collider R&D united in a common effort to produce a global design for the ILC. In November 2004, the 1st International Linear Collider Workshop was held at KEK, Tsukuba, Japan. The workshop was attended by some 200 accelerator physicists from around the world, and paved the way for the 2nd ILC Workshop in August 2005, held at Snowmass, Colorado, USA, where the ILC Global Design Effort (GDE) was officially formed. The GDE membership reflects the global nature of the collaboration, with accelerator experts from all three regions (Americas, Asia and Europe). The first major goal of the GDE was to define the basic parameters and layout of the machine--the Baseline Configuration. This was achieved at the first GDE meeting held at INFN, Frascati, Italy in December 2005 with the creation …
Date: December 14, 2007
Creator: Phinney, Nan
Object Type: Article
System: The UNT Digital Library
Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium-Contaminated Sites (open access)

Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium-Contaminated Sites

This report summarizes 4 years of research achievements in this Office of Science (BER), U.S. Department of Energy (DOE) project. The research described was conducted by scientists and supporting staff at Lovelace Respiratory Research Institute (LRRI)/Lovelace Biomedical and Environmental Research Institute (LBERI) and the Southern Urals Biophysics Institute (SUBI). All project objectives and goals were achieved. A major focus was on obtaining improved cancer risk estimates for exposure via inhalation to plutonium (Pu) isotopes in the workplace (DOE radiation workers) and environment (public exposures to Pu-contaminated soil). A major finding was that low doses and dose rates of gamma rays can significantly suppress cancer induction by alpha radiation from inhaled Pu isotopes. The suppression relates to stimulation of the body's natural defenses, including immunity against cancer cells and selective apoptosis which removes precancerous and other aberrant cells.
Date: December 14, 2007
Creator: Scott, Bobby R.; Tokarskaya, Zoya B.; Zhuntova, Galina V.; Osovets, Sergey V. & Syrchikov, Victor A., Belyaeva, Zinaida D.
Object Type: Report
System: The UNT Digital Library
New and Novel Nondestructive Neutron and Gamma-Ray Technologies Applied to Safeguards (open access)

New and Novel Nondestructive Neutron and Gamma-Ray Technologies Applied to Safeguards

None
Date: December 14, 2007
Creator: Dougan, A. D.; Snyderman, N. J.; Nakae, L. F.; Dietrich, D. D.; Kerr, P. L.; Wang, T. F. et al.
Object Type: Article
System: The UNT Digital Library
Environmental Energy Technologies Division Newsletter, Fall 2007,Vol.4, No. 4) (open access)

Environmental Energy Technologies Division Newsletter, Fall 2007,Vol.4, No. 4)

This issue's special focus is on advanced lithium ionbatteries for hybrid electric vehicle applications. The four articlesaddressing this area explore the modeling of lithium ion batterychemistries; the use of advanced diagnostic methods to study the physicsand chemistry of battery materials; a laboratory for advanced batterytesting; and approaches for improving battery safety. EETD's research isfunded by the Department of Energy's BATT (Batteries for AdvancedTransportation Technologies) program, FreedomCar and Vehicle TechnologiesProgram.
Date: December 14, 2007
Creator: Chen, Allan (Editor)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Investigating Inflation in Type IIA (open access)

Investigating Inflation in Type IIA

We prove that inflation is forbidden in the most well understood class of semi-realistic type IIA string compactifications: Calabi-Yau compactifications with only standard NS-NS 3-form flux, R-R fluxes, D6-branes and O6-planes at large volume and small string coupling. With these ingredients, the first slow-roll parameter satisfies {epsilon} {ge} 27/13 whenever V > 0, ruling out both inflation (including brane/anti-brane inflation) and de Sitter vacua in this limit. Our proof is based on the dependence of the 4-dimensional potential on the volume and dilaton moduli in the presence of fluxes and branes. We also describe broader classes of IIA models which may include cosmologies with inflation and/or de Sitter vacua. The inclusion of extra ingredients, such as NS 5-branes and geometric or non-geometric NS-NS fluxes, evades the assumptions used in deriving the no-go theorem. We focus on NS 5-branes and outline how such ingredients may prove fruitful for cosmology, but we do not provide an explicit model. We contrast the results of our IIA analysis with the rather different situation in IIB.
Date: December 14, 2007
Creator: Hertzberg, Mark P.; /MIT; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Taylor, Washington; Tegmark, Max et al.
Object Type: Article
System: The UNT Digital Library
Localized Pd Overgrowth on Cubic Pt Nanocrystals for Enhanced Electrocatalytic Oxidation of Formic Acid (open access)

Localized Pd Overgrowth on Cubic Pt Nanocrystals for Enhanced Electrocatalytic Oxidation of Formic Acid

Single crystalline surface such as (100), (111), (110) has been studied as an idealized platform for electrocatalytic reactions since the atomic arrangement affects a catalytic property. The secondary metal deposition on these surfaces also alters the catalytic property often showing improvement such as poisoning decrease. On the other hand, electrocatalysts used for practical purpose usually have a size on the order of nanometers. Therefore, linking the knowledge from single crystalline studies to nanoparticle catalysts is of enormous importance. Recently, the Pt nanoparticles which surface structure was preferentially oriented was synthesized and used as electrocatalysts. Here, we demonstrate a rational design of a binary metallic nanocatalyst based on the single crystalline study.
Date: December 14, 2007
Creator: Lee, Hyunjoo; Habas, Susan; Somorjai, Gabor & Yang, Peidong
Object Type: Article
System: The UNT Digital Library
Erratum: High power impulse magnetron sputtering:Current-voltage-time characteristics indicate the onset of sustainedself-sputtering (open access)

Erratum: High power impulse magnetron sputtering:Current-voltage-time characteristics indicate the onset of sustainedself-sputtering

None
Date: December 14, 2007
Creator: Anders, Andre; Andersson, Joakim & Ehiasarian, Arutiun
Object Type: Article
System: The UNT Digital Library
SRS BEDROCK PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) DESIGN BASIS JUSTIFICATION (U) (open access)

SRS BEDROCK PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) DESIGN BASIS JUSTIFICATION (U)

This represents an assessment of the available Savannah River Site (SRS) hard-rock probabilistic seismic hazard assessments (PSHAs), including PSHAs recently completed, for incorporation in the SRS seismic hazard update. The prior assessment of the SRS seismic design basis (WSRC, 1997) incorporated the results from two PSHAs that were published in 1988 and 1993. Because of the vintage of these studies, an assessment is necessary to establish the value of these PSHAs considering more recently collected data affecting seismic hazards and the availability of more recent PSHAs. This task is consistent with the Department of Energy (DOE) order, DOE O 420.1B and DOE guidance document DOE G 420.1-2. Following DOE guidance, the National Map Hazard was reviewed and incorporated in this assessment. In addition to the National Map hazard, alternative ground motion attenuation models (GMAMs) are used with the National Map source model to produce alternate hazard assessments for the SRS. These hazard assessments are the basis for the updated hard-rock hazard recommendation made in this report. The development and comparison of hazard based on the National Map models and PSHAs completed using alternate GMAMs provides increased confidence in this hazard recommendation. The alternate GMAMs are the EPRI (2004), USGS (2002) …
Date: December 14, 2005
Creator: Lee, R. C. & McHood, M. D.
Object Type: Report
System: The UNT Digital Library
A Collapse Surface for Perforated Plates with Triangular Patterns for Ligament Efficiencies Between 0.05 and 0.50 (open access)

A Collapse Surface for Perforated Plates with Triangular Patterns for Ligament Efficiencies Between 0.05 and 0.50

Collapse surfaces are developed for thick perforated plates containing a triangular penetration pattern with ligament efficiencies of 0.05, 0.10, 0.15, 0.2, 0.3, and 0.5 using elastic-perfectly plastic FEA analysis. The FEA data was fit to a fourth-order collapse function which is appropriate for the development of an equivalent solid elastic-perfectly plastic plasticity model for perforated plates with triangular penetration patterns. This type of model can be conveniently used to develop a limit load capability for perforated plate analysis. It was shown that the fourth-order function is reasonable for ligament efficiencies between 0.15 to 0.5. Comparing the fourth-order collapse function to FEA data suggests that an alternate collapse function is needed for ligament efficiencies less than 0.15. A linear interpolation method was shown to be appropriate for ligament efficiencies between 0.15 and 0.5.
Date: December 14, 2000
Creator: Gordon, D.P. Jones and J.L.
Object Type: Report
System: The UNT Digital Library
Measurements and Phenomenological Modeling of Magnetic FluxBuildup in Spheromak Plasmas (open access)

Measurements and Phenomenological Modeling of Magnetic FluxBuildup in Spheromak Plasmas

Internal magnetic field measurements and high-speed imaging at the Sustained Spheromak Physics Experiment (SSPX) [E. B. Hooper, L. D. Pearlstein, R. H. Bulmer, Nucl. Fusion 39, 863 (1999)] are used to study spheromak formation and field buildup. The measurements are analyzed in the context of a phenomenological model of magnetic helicity based on the topological constraint of minimum helicity in the open flux before reconnecting and linking closed flux. Two stages are analyzed: (1) the initial spheromak formation, i. e. when all flux surfaces are initially open and reconnect to form open and closed flux surfaces, and (2) the stepwise increase of closed flux when operating the gun on a new mode that can apply a train of high-current pulses to the plasma. In the first stage, large kinks in the open flux surfaces are observed in the high-speed images taken shortly after plasma breakdown, and coincide with large magnetic asymmetries recorded in a fixed insertable magnetic probe that spans the flux conserver radius. Closed flux (in the toroidal average sense) appears shortly after this. This stage is also investigated using resistive magnetohydrodynamic simulations. In the second stage, a time lag in response between open and closed flux surfaces after …
Date: December 14, 2007
Creator: Romero-Talamas, C. A.; Hooper, E. B.; Jayakumar, R.; McLean, H. S.; Wood, R. D. & Moller, J. M.
Object Type: Article
System: The UNT Digital Library
Report Initial Work on Developing Plasma Modeling Capability in WARP for NDCX Experiments (open access)

Report Initial Work on Developing Plasma Modeling Capability in WARP for NDCX Experiments

This milestone has been accomplished. The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) has developed and implemented an initial beam-in-plasma implicit modeling capability in Warp; has carried out tests validating the behavior of the models employed; has compared the results of electrostatic and electromagnetic models when applied to beam expansion in an NDCX-I relevant regime; has compared Warp and LSP results on a problem relevant to NDCX-I; has modeled wave excitation by a rigid beam propagating through plasma; and has implemented and begun testing a more advanced implicit method that correctly captures electron drift motion even when timesteps too large to resolve the electron gyro-period are employed. The HIFS-VNL is well on its way toward having a state-of-the-art source-to-target simulation capability that will enable more effective support of ongoing experiments in the NDCX series and allow more confident planning for future ones.
Date: December 14, 2007
Creator: Friedman, A; Cohen, R H; Grote, D P & Vay, J
Object Type: Report
System: The UNT Digital Library
Synchronous Parallel Kinetic Monte Carlo (open access)

Synchronous Parallel Kinetic Monte Carlo

A novel parallel kinetic Monte Carlo (kMC) algorithm formulated on the basis of perfect time synchronicity is presented. The algorithm provides an exact generalization of any standard serial kMC model and is trivially implemented in parallel architectures. We demonstrate the mathematical validity and parallel performance of the method by solving several well-understood problems in diffusion.
Date: December 14, 2006
Creator: Mart?nez, E.; Marian, J. & Kalos, M. H.
Object Type: Article
System: The UNT Digital Library
The Path of Carbon in Photosynthesis IV. The Identity and Sequencefo the Intermediates in Sucrose Synthesis (open access)

The Path of Carbon in Photosynthesis IV. The Identity and Sequencefo the Intermediates in Sucrose Synthesis

The synthesis of sucrose from C{sup 14}0{sub 22} by green algae has been investigated and the intermediates separated by the method of paper chromatography. It is shown that sucrose is the first free sugar appearing during photosynthesis. It is apparently formed by condensation of the glucose-I-phosphate and a fructose phosphate. A series of radioautographs of paper chromatograms of extracts from plants which have photosynthesized for different periods of time has been prepared. The results indicate that 2-phosphoglyceric acid is the first product synthesized from C0{sub 2} during photosynthesis.
Date: December 14, 1948
Creator: Calvin, M. & Benson, A.
Object Type: Report
System: The UNT Digital Library
Three-dimensional Dielectric Photonic Crystal Structures for Laser-driven Acceleration (open access)

Three-dimensional Dielectric Photonic Crystal Structures for Laser-driven Acceleration

We present the design and simulation of a three-dimensional photonic crystal waveguide for linear laser-driven acceleration in vacuum. The structure confines a synchronous speed-of-light accelerating mode in both transverse dimensions. We report the properties of this mode, including sustainable gradient and optical-to-beam efficiency. We present a novel method for confining a particle beam using optical fields as focusing elements. This technique, combined with careful structure design, is shown to have a large dynamic aperture and minimal emittance growth, even over millions of optical wavelengths.
Date: December 14, 2007
Creator: Cowan, Benjamin M. & /Tech-X, Boulder /SLAC
Object Type: Article
System: The UNT Digital Library
Unique Identification of Lee-Wick Gauge Bosons at Linear Colliders (open access)

Unique Identification of Lee-Wick Gauge Bosons at Linear Colliders

Grinstein, O'Connell and Wise have recently presented an extension of the Standard Model (SM), based on the ideas of Lee and Wick (LW), which demonstrates an interesting way to remove the quadratically divergent contributions to the Higgs mass induced by radiative corrections. This model predicts the existence of negative-norm copies of the usual SM fields at the TeV scale with ghost-like propagators and negative decay widths, but with otherwise SM-like couplings. In earlier work, it was demonstrated that the LW states in the gauge boson sector of these models, though easy to observe, cannot be uniquely identified as such at the LHC. In this paper, we address the issue of whether or not this problem can be resolved at an e{sup +}e{sup -} collider with a suitable center of mass energy range. We find that measurements of the cross section and the left-right polarization asymmetry associated with Bhabha scattering can lead to a unique identification of the neutral electroweak gauge bosons of the Lee-Wick type.
Date: December 14, 2007
Creator: Rizzo, Thomas G.
Object Type: Article
System: The UNT Digital Library
Use of ARM Data to address the Climate Change Further Development and Applications of A Multi-scale Modeling Framework (open access)

Use of ARM Data to address the Climate Change Further Development and Applications of A Multi-scale Modeling Framework

The Colorado State University (CSU) Multi-scale Modeling Framework (MMF) is a new type of general circulation model (GCM) that replaces the conventional parameterizations of convection, clouds and boundary layer with a cloud-resolving model (CRM) embedded into each grid column. The MMF that we have been working with is a “super-parameterized” version of the Community Atmosphere Model (CAM). As reported in the publications listed below, we have done extensive work with the model. We have explored the MMF’s performance in several studies, including an AMIP run and a CAPT test, and we have applied the MMF to an analysis of climate sensitivity.
Date: December 14, 2007
Creator: Randall, David A. & Khairoutdinov, Marat
Object Type: Report
System: The UNT Digital Library
Non-Relativistic Superstring Theories (open access)

Non-Relativistic Superstring Theories

We construct a supersymmetric version of the 'critical' non-relativistic bosonic string theory [1] with its manifest global symmetry. We introduce the anticommuting bc CFT which is the super partner of the {beta}{gamma} CFT. The conformal weights of the b and c fields are both 1/2. The action of the fermionic sector can be transformed into that of the relativistic superstring theory. We explicitly quantize the theory with manifest SO(8) symmetry and find that the spectrum is similar to that of Type IIB superstring theory. There is one notable difference: the fermions are non-chiral. We further consider 'noncritical' generalizations of the supersymmetric theory using the superspace formulation. There is an infinite range of possible string theories similar to the supercritical string theories. We comment on the connection between the critical non-relativistic string theory and the lightlike Linear Dilaton theory.
Date: December 14, 2007
Creator: Kim, Bom Soo
Object Type: Article
System: The UNT Digital Library
Geology Data Package for the Single-Shell Tank Waste Management Areas at the Hanford Site (open access)

Geology Data Package for the Single-Shell Tank Waste Management Areas at the Hanford Site

This data package discusses the geology of the single-shell tank (SST) farms and the geologic history of the area. The purpose of this report is to provide the most recent geologic information available for the SST farms. This report builds upon previous reports on the tank farm geology and Integrated Disposal Facility geology with information available after those reports were published.
Date: December 14, 2007
Creator: Reidel, Stephen P. & Chamness, Mickie A.
Object Type: Report
System: The UNT Digital Library