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Hadron-hadron physics at high energy and luminosity (open access)

Hadron-hadron physics at high energy and luminosity

I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date: November 8, 1989
Creator: Hinchliffe, I.
Object Type: Article
System: The UNT Digital Library
Geometric continuum regularization of quantum field theory (open access)

Geometric continuum regularization of quantum field theory

An overview of the continuum regularization program is given. The program is traced from its roots in stochastic quantization, with emphasis on the examples of regularized gauge theory, the regularized general nonlinear sigma model and regularized quantum gravity. In its coordinate-invariant form, the regularization is seen as entirely geometric: only the supermetric on field deformations is regularized, and the prescription provides universal nonperturbative invariant continuum regularization across all quantum field theory. 54 refs.
Date: November 8, 1989
Creator: Halpern, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
Kilowatt Isotope Power System: component test report for the ground demonstration system jet condenser orifice performance. 77-KIPS-103 (open access)

Kilowatt Isotope Power System: component test report for the ground demonstration system jet condenser orifice performance. 77-KIPS-103

The purpose of these tests was to determine which orifice elements achieved satisfactory hydraulic and thermal performance prior to their incorporation into the Jet Condenser Assembly. Requirements were as set forth within the Kilowatt Isotope Power System (KIPS) Component Test Procedure number 414 for the Jet Condenser Orifice Performance testing. The results of the performance testing conducted on the Jet Condenser Orifices are presented. Part Number 720841 Jet Condenser Orifice Nozzle successfully completed the orifice screening tests.
Date: November 8, 1977
Creator: Brainard, E.L.
Object Type: Report
System: The UNT Digital Library
Optical remote measurement of temperature in the range 0 to 2000/sup 0/C (open access)

Optical remote measurement of temperature in the range 0 to 2000/sup 0/C

None
Date: November 8, 1974
Creator: Burgess, T. J.; Schultz, P. A. & Wouters, L. F.
Object Type: Report
System: The UNT Digital Library
Soft-sphere model for liquid metals (open access)

Soft-sphere model for liquid metals

A semi-empirical soft-sphere model of fluids is modified for application to the thermodynamic properties of liquid metals. Enthalpy, volume, and sound speed are computed as functions of temperature for 13 metals and compared with experimental data. Critical points and coexistence curves are also computed and compared with experimental data, where these have been measured. Strengths and weaknesses of the model are discussed.
Date: November 8, 1977
Creator: Young, D.A.
Object Type: Report
System: The UNT Digital Library
Construction techniques for short iron-free dipole magnets (open access)

Construction techniques for short iron-free dipole magnets

A method was developed for economically fabricating short, wire-wound, steering magnets with maximum length, cosine-distributed, axial elements. This method utilizes multifunctional tooling to precisely flat-wind two-layer dipole halves that are subsequently reformed and encapsulated into semicylindrical form with confinement of the end turns into thin, half discs normal to the magnet axis. This paper addresses the magnet fabrication in detail, highlighting the inherent quality control features of the tooling, overall construction costs, and contemplated manufacturing enhancements.
Date: November 8, 1983
Creator: Harvey, A.R.
Object Type: Article
System: The UNT Digital Library
Assessing Recharge and Geological Model Uncertainty at the Climax Mine Area of the Nevada Test Site (open access)

Assessing Recharge and Geological Model Uncertainty at the Climax Mine Area of the Nevada Test Site

Hydrologic analyses are commonly based on a single conceptual-mathematical model. Yet hydrologic environments are open and complex, rendering them prone to multiple interpretations and mathematical descriptions. Considering conceptual model uncertainty is a critical process in hydrologic uncertainty assessment. This study assesses recharge and geologic model uncertainty for the Climax mine area of the Nevada Test Site, Nevada. Five alternative recharge models have been independently developed for Nevada and the Death Valley area of California. These models are (1) the Maxey-Eakin model, (2 and 3) a distributed parameter watershed model with and without a runon-runoff component, and (4 and 5) a chloride mass-balance model with two zero-recharge masks, one for alluvium and one for both alluvium and elevation. Similarly, five geological models have been developed based on different interpretations of available geologic information. One of them was developed by the U.S. Geological Survey for the Death Valley Regional Flow System (DVRFS) model; the other four were developed by Bechtel Nevada for the Yucca Flat Corrective Action Unit (CAU). The Climax mine area is in the northern part of the Yucca Flat CAU, which is within the DVRFS. A total of 25 conceptual models are thus formulated based on the five recharge …
Date: November 8, 2007
Creator: Ye, M.; Pohlmann, K.; Chapman, J. & Pohll, G.
Object Type: Article
System: The UNT Digital Library
Analysis of the SL-1 Accident Using RELAPS5-3D (open access)

Analysis of the SL-1 Accident Using RELAPS5-3D

On January 3, 1961, at the National Reactor Testing Station, in Idaho Falls, Idaho, the Stationary Low Power Reactor No. 1 (SL-1) experienced a major nuclear excursion, killing three people, and destroying the reactor core. The SL-1 reactor, a 3 MW{sub t} boiling water reactor, was shut down and undergoing routine maintenance work at the time. This paper presents an analysis of the SL-1 reactor excursion using the RELAP5-3D thermal-hydraulic and nuclear analysis code, with the intent of simulating the accident from the point of reactivity insertion to destruction and vaporization of the fuel. Results are presented, along with a discussion of sensitivity to some reactor and transient parameters (many of the details are only known with a high level of uncertainty).
Date: November 8, 2007
Creator: Francisco, A.D. and Tomlinson, E. T.
Object Type: Article
System: The UNT Digital Library
SUSY Les Houches Accord 2 (open access)

SUSY Les Houches Accord 2

The Supersymmetry Les Houches Accord (SLHA) [1] provides a universal set of conventions for conveying spectral and decay information for supersymmetry analysis problems in high energy physics. Here, we propose extensions of the conventions of the first SLHA to include various generalizations: the minimal supersymmetric standard model with violation of CP, R-parity, and flavor, as well as the simplest next-to-minimal model.
Date: November 8, 2007
Creator: Allanach, B.; Balazs, C.; Belanger, G.; Bernhardt, M.; Boudjema, F.; Choudhury, D. et al.
Object Type: Article
System: The UNT Digital Library
SYNTHESIS OF METAL HYDRIDES BY MECHANICAL ALLOYING IN AN ATTRITOR MILL: FY07 STATUS REPORT (open access)

SYNTHESIS OF METAL HYDRIDES BY MECHANICAL ALLOYING IN AN ATTRITOR MILL: FY07 STATUS REPORT

The objective of this task was to demonstrate that metal hydrides could be produced by mechanical alloying in the quantities needed to support the tritium production facilities at the Savannah River Site. The objective for the FY07 portion of this task was to demonstrate the production of Zr-Fe getter materials by mechanical alloying and begin to optimize the milling parameters. Three starting compositions (ratios of elemental Zr and Fe powders) were selected and attritor milled under argon for times of 8 to 60 hours. Hexane and liquid nitrogen were used as process control agents. In general, milling times of at least 24 hours were required to form the desired Zr{sub 2}Fe and Zr{sub 3}Fe phases, although a considerable amount of unalloyed Zr and Fe remained. Milling in liquid nitrogen does not appear to provide any advantages over milling in hexane, particularly due to the formation of ZrN after longer milling times. Carbides of Zr formed during some of the milling experiments in hexane. Formation of carbides during milling appears to be much less of an issue than formation of nitrides, although some of the phases that were not able to be identified in the XRD results may also be carbides. …
Date: November 8, 2007
Creator: Fox, K
Object Type: Report
System: The UNT Digital Library
Comparison of observed and theoretical Fe L emission from CIE plasmas (open access)

Comparison of observed and theoretical Fe L emission from CIE plasmas

We analyze data from the Lawrence Livermore National Lab (LLNL) Electron Beam Ion Trap (EBIT) that simulates a CIE plasma by sweeping the electron beam to approximate a Maxwellian velocity distribution. These results are compared to spectra of confirmed astronomical CIE plasmas (e.g. outer regions of x-ray clusters) observed by XMM/RGS. We utilize the Photon Clean Method (PCM) to quantify these spectra (EBIT and XMM/RGS) in the form of ratios of Fe L lines in the emission complex near 1 keV. The variances of line fluxes are measured with bootstrap methods (Efron 1979). Both of these observations are further compared with theoretical predictions of Fe L line fluxes from APED and similar atomic databases.
Date: November 8, 2007
Creator: Carpenter, M; Beiersdorfer, P; Brown, G V; Chen, H C; Gu, M F & Jernigan, J G
Object Type: Report
System: The UNT Digital Library
Direct Measurements of an increased threshold for stimulated Brillouin scattering with polarization smoothing in ignition hohlraum plasmas (open access)

Direct Measurements of an increased threshold for stimulated Brillouin scattering with polarization smoothing in ignition hohlraum plasmas

We demonstrate a significant reduction of stimulated Brillouin scattering by polarization smoothing. The intensity threshold is measured to increase by a factor of 1.7 {+-} 0.2 when polarization smoothing is applied. The results were obtained in a high-temperature (T{sub 3} {approx_equal} 3 keV) hohlraum plasma where filamentation is negligible in determining the backscatter threshold. These results are explained by an analytical model relevant to ICF plasma conditions that modifies the linear gain exponent to account for polarization smoothing.
Date: November 8, 2007
Creator: Froula, D; Divol, L; Berger, R L; London, R; Meezan, N; Neumayer, P et al.
Object Type: Article
System: The UNT Digital Library
Concealed Threat Detection at Multiple Frames-per-second (open access)

Concealed Threat Detection at Multiple Frames-per-second

In this LDRD project, our research purpose is to investigate the science and technology necessary to enable real-time array imaging as a rapid way to detect hidden threats through obscurants such as smoke, fog, walls, doors, and clothing. The goal of this research is to augment the capabilities of protective forces in concealed threat detection. In the current context, threats include people as well as weapons. In most cases, security personnel must make very fast assessments of a threat based upon limited amount of data. Among other attributes, UWB has been shown and quantified to penetrate and propagate through many materials (wood, some concretes, non-metallic building materials, some soils, etc.) while maintaining high range resolution. We have build collaborations with university partners and government agencies. We have considered the impact of psychometrics on target recognition and identification. Specifically we have formulated images in real-time that will engage the user's vision system in a more active way to enhance image interpretation capabilities. In this project, we are researching the use of real time (field programmable gate arrays) integrated with high resolution (cm scale), ultra wide band (UWB) electromagnetic signals for imaging personnel through smoke and walls. We evaluated the ability of …
Date: November 8, 2005
Creator: Chang, J T
Object Type: Report
System: The UNT Digital Library
Three dimensional modeling of Laser-Plasma interaction: benchmarking our predictive modeling tools vs. experiments (open access)

Three dimensional modeling of Laser-Plasma interaction: benchmarking our predictive modeling tools vs. experiments

We have developed a new target platform to study Laser Plasma Interaction in ignition-relevant condition at the Omega laser facility (LLE/Rochester)[1]. By shooting an interaction beam along the axis of a gas-filled hohlraum heated by up to 17 kJ of heater beam energy, we were able to create a millimeter-scale underdense uniform plasma at electron temperatures above 3 keV. Extensive Thomson scattering measurements allowed us to benchmark our hydrodynamic simulations performed with HYDRA[2]. As a result of this effort, we can use with much confidence these simulations as input parameters for our LPI simulation code pF3d[3]. In this paper, we show that by using accurate hydrodynamic profiles and full three-dimensional simulations including a realistic modeling of the laser intensity pattern generated by various smoothing options, whole beam three-dimensional linear kinetic modeling of stimulated Brillouin scattering reproduces quantitatively the experimental measurements(SBS thresholds, reflectivity values and the absence of measurable SRS). This good agreement was made possible by the recent increase in computing power routinely available for such simulations. These simulations accurately predicted the strong reduction of SBS measured when polarization smoothing is used.
Date: November 8, 2007
Creator: Divol, L; Berger, R; Meezan, N; Froula, D H; Dixit, S; Suter, L et al.
Object Type: Article
System: The UNT Digital Library

PEEM Thermal Stress and Reliability

Advancing power electronics thermal stress and reliability is a critical factor in power electronics equipment. NREL aims to improve thermal stress and reliability of power electronics technologies.
Date: November 8, 2007
Creator: O'Keefe, M. P.
Object Type: Presentation
System: The UNT Digital Library

Characterization and Development of Advanced Heat Transfer Technologies

Advancing heat transfer technologies is a critical factor in power electronics equipment. NREL aims to characterize and develop advanced heat transfer technologies.
Date: November 8, 2007
Creator: Abraham, T.
Object Type: Presentation
System: The UNT Digital Library
Transition to Turbulence and Effect of Initial Conditions on 3D Compressible Mixing in Planar Blast-wave-driven Systems (open access)

Transition to Turbulence and Effect of Initial Conditions on 3D Compressible Mixing in Planar Blast-wave-driven Systems

Perturbations on an interface driven by a strong blast wave grow in time due to a combination of Rayleigh-Taylor, Richtmyer-Meshkov, and decompression effects. In this paper, results from three-dimensional numerical simulations of such a system under drive conditions to be attainable on the National Ignition Facility [E. M. Campbell, Laser Part. Beams, 9(2), 209 (1991)] are presented. Using the multi-physics, adaptive mesh refinement, higher order Godunov Eulerian hydrocode, Raptor [L. H. Howell and J.A. Greenough, J. Comp. Phys. 184, 53 (2003)], the late nonlinear instability evolution, including transition to turbulence, is considered for various multimode perturbation spectra. The 3D post-transition state differs from the 2D result, but the process of transition proceeds similarly in both 2D and 3D. The turbulent mixing transition results in a reduction in the growth rate of the mixing layer relative to its pre-transition value and, in the case of the bubble front, relative to the 2D result. The post-transition spike front velocity is approximately the same in 2D and 3D. Implications for hydrodynamic mixing in core-collapse supernova are discussed.
Date: November 8, 2004
Creator: Miles, A R; Edwards, M J & Greenough, J A
Object Type: Article
System: The UNT Digital Library

Advanced Thermal Interface Materials for Power Electronics

Advancing thermal interface materials for power electronics is a critical factor in power electronics equipment. NREL aims to improve thermal interface materials for power electronics technologies.
Date: November 8, 2007
Creator: Narumanchi, S.
Object Type: Presentation
System: The UNT Digital Library

Power Electronic Thermal System Performance and Integration

Thermal control is a critical factor in power electronics equipment. NREL aims to integrate and improve thermal system performance in power electronics.
Date: November 8, 2007
Creator: Bennion, K.
Object Type: Presentation
System: The UNT Digital Library
Ion Beam Induced Surface Modulations from Nano to Pico: Optimizing Deposition During Erosion and Erosion During Deposition. (open access)

Ion Beam Induced Surface Modulations from Nano to Pico: Optimizing Deposition During Erosion and Erosion During Deposition.

Ion beams of sufficient energy to erode a surface can lead to surface modulations that depend on the ion beam, the material surface it impinges, and extrinsic parameters such as temperature and geometric boundary conditions. Focused Ion Beam technology both enables site-specific placement of these modulations and expedites research through fast, high dose and small efficient use of material. The DualBeam (FIB/SEM) enables in situ metrology, with movies observing ripple formation, wave motion, and the influence of line defects. Nanostructures (ripples of >400nm wavelength to dots spaced <40nm) naturally grow from atomically flat surfaces during erosion, however, a steady state size may or may not be achieved as a consequence of numerous controlled parameters: temperature, angle, energy, crystallography. Geometric factors, which can be easily invoked using a FIB, enable a controlled component of deposition (and/or redeposition) to occur during erosion, and conversely allow a component of etching to be incurred during (ion-beam assisted) deposition. High angles of ion beam inclination commonly lead to 'rougher' surfaces, however, the extreme case of 90.0{sup o} etching enables deposition of organized structures 1000 times smaller than the aforementioned, video-recorded nanostructures. Orientation and position of these picostructures (naturally quantized by their atomic spacings) may be …
Date: November 8, 2007
Creator: MoberlyChan, W J & Schalek, R
Object Type: Article
System: The UNT Digital Library
Modeling EERE Deployment Programs (open access)

Modeling EERE Deployment Programs

The purpose of this report is to compile information and conclusions gathered as part of three separate tasks undertaken as part of the overall project, “Modeling EERE Deployment Programs,” sponsored by the Planning, Analysis, and Evaluation office within the Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE). The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address improvements to modeling in the near term, and note gaps in knowledge where future research is needed.
Date: November 8, 2007
Creator: Cort, Katherine A.; Hostick, Donna J.; Belzer, David B. & Livingston, Olga V.
Object Type: Report
System: The UNT Digital Library
Corrosion-resistant multilayer coatings for the 28-75 nm wavelength region (open access)

Corrosion-resistant multilayer coatings for the 28-75 nm wavelength region

Corrosion has prevented use of SiC/Mg multilayers in applications requiring good lifetime stability. We have developed Al-based barrier layers that dramatically reduce corrosion, while preserving high reflectance and low stress. The aforementioned advances may enable the implementation of corrosion-resistant, high-performance SiC/Mg coatings in the 28-75 nm region in applications such as tabletop EUV/soft x-ray laser sources and solar physics telescopes. Further study and optimization of corrosion barrier structures and coating designs is underway.
Date: November 8, 2011
Creator: Soufli, R.; Fernandez-Perea, Monica & Al, E. T.
Object Type: Article
System: The UNT Digital Library
The replacement of an electromagnetic primary sodium sampling pump in the Fast Flux Test Facility (open access)

The replacement of an electromagnetic primary sodium sampling pump in the Fast Flux Test Facility

On November 16, 1984 a leak was discovered in one of the Fast Flux Test Facility (FFTF) Primary Sodium Sampling System electromagnetic pumps. The leak was discovered in the course of routine cell entry to investigate a shorted trace heat element. The purpose of this paper is to describe the circumstances surrounding the occurrence of the leak, the actions taken to replace the damaged pump and the additional steps which were necessary to return the plant to power. In addition, the processes involved in producing the leak are described briefly. The relative ease of recovery from this incident is indicative of the overall feasibility of the Liquid Metal Reactor (LMR) operational concept.
Date: November 8, 1985
Creator: Grygiel, M. L. & McCargar, C. G.
Object Type: Article
System: The UNT Digital Library
(International Collaboration on Advanced Neutron Sources) (open access)

(International Collaboration on Advanced Neutron Sources)

The International Collaboration on Advanced Neutron Sources was started about a decade ago with the purpose of sharing information throughout the global neutron community. The collaboration has been extremely successful in optimizing the use of resources, and the discussions are open and detailed, with reasons for failure shared as well as reasons for success. Although the meetings have become increasingly oriented toward pulsed neutron sources, many of the neutron instrumentation techniques, such as the development of better monochromators, fast response detectors and various data analysis methods, are highly relevant to the Advanced Neutron Source (ANS). I presented one paper on the ANS, and another on the neutron optical polarizer design work which won a 1989 R D-100 Award. I also gained some valuable design ideas, in particular for the ANS hot source, in discussions with individual researchers from Canada, Western Europe, and Japan.
Date: November 8, 1990
Creator: Hayter, J. B.
Object Type: Report
System: The UNT Digital Library