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HANFORD REGULATORY EXPERIENCE REGULATION AT HANFORD A CASE STUDY (open access)

HANFORD REGULATORY EXPERIENCE REGULATION AT HANFORD A CASE STUDY

Hanford has played a pivotal role in the United States' defense for more than 60 years, beginning with the Manhattan Project in the 1940s. During its history, the Hanford Site has had nine reactors producing plutonium for the United States' nuclear weapons program. All the reactors were located next to the Columbia River and all had associated low-level radioactive and hazardous waste releases. Site cleanup, which formally began in 1989 with the signing of the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement, involves more than 1,600 waste sites and burial grounds, and the demolition of more than 1,500buildings and structures, Cleanup is scheduled to be complete by 2035. Regulatory oversight of the cleanup is being performed by the U.S. Environmental Protection Agency (EPA) and the Washington State Department of Ecology(Ecology) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Revised Code of Washington, 'Hazardous Waste Management.' Cleanup of the waste sites and demolition of the many buildings and structures generates large volumes of contaminated soil, equipment, demolition debris, and other wastes that must be disposed of in a secure manner to prevent further environmental degradation. From a risk perspective, it is …
Date: September 24, 2007
Creator: AR, HAWKINS
System: The UNT Digital Library
Neutrino Observations From the Sudbury Neutrino Observatory (open access)

Neutrino Observations From the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D{sub 2}O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar {nu}{sub e} flux and the total flux of all active neutrino species. Solar neutrinos from the decay of {sup 8}B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to {nu}{sub e}, the ES reaction also has a small sensitivity to {nu}{sub {mu}} and {nu}{sub {tau}}. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from {sup 8}B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The {nu}{sub e} flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3{sigma}. This is evidence for an active neutrino component, in additional to {nu}{sub e}, in the solar neutrino flux. These results also allow the first experimental determination …
Date: September 24, 2001
Creator: Ahmad, Q. R.; Allen, R. C.; Andersen, T. C.; Anglin, J. D.; Barton, J. C.; Beier, E. W. et al.
System: The UNT Digital Library
Light-ion therapy in the U.S.: From the Bevalac to ?? (open access)

Light-ion therapy in the U.S.: From the Bevalac to ??

While working with E.O. Lawrence at Berkeley, R.R. Wilson in 1946 noted the potential for using the Bragg-peak of protons (or heavier ions) for radiation therapy. Thus began the long history of contributions from Berkeley to this field. Pioneering work by C.A. Tobias et al at the 184-Inch Synchrocyclotron led ultimately to clinical applications of proton and helium beams, with over 1000 patients treated through 1974 with high-energy plateau radiation; placing the treatment volume (mostly pituitary fields) at the rotational center of a sophisticated patient positioner. In 1974 the SuperHILAC and Bevatron accelerators at the Lawrence Berkeley Laboratory were joined by the construction of a 250-meter transfer line, forming the Bevalac, a facility capable of accelerating ions of any atomic species to relativistic energies. With the advent of these new beams, and better diagnostic tools capable of more precise definition of tumor volume and determination of the stopping point of charged-particle beams, large-field Bragg-peak therapy with ion beams became a real possibility. A dedicated Biomedical experimental area was developed, ultimately consisting of three distinct irradiation stations; two dedicated to therapy and one to radiobiology and biophysics. These facilities included dedicated support areas for patient setup and staging of animal and …
Date: September 24, 2002
Creator: Alonso, Jose R. & Castro, Joseph R.
System: The UNT Digital Library
Toward Control of Matter: Basic Energy Science Needs for a New Class of X-Ray Light Sources (open access)

Toward Control of Matter: Basic Energy Science Needs for a New Class of X-Ray Light Sources

Over the past quarter century, light-source user facilities have transformed research in areas ranging from gas-phase chemical dynamics to materials characterization. The ever-improving capabilities of these facilities have revolutionized our ability to study the electronic structure and dynamics of atoms, molecules, and even the most complex new materials, to understand catalytic reactions, to visualize magnetic domains, and to solve protein structures. Yet these outstanding facilities still have limitations well understood by their thousands of users. Accordingly, over the past several years, many proposals and conceptual designs for"next-generation" x-ray light sources have been developed around the world. In order to survey the scientific problems that might be addressed specifically by those new light sources operating below a photon energy of about 3 keV and to identify the scientific requirements that should drive the design of such facilities, a workshop"Science for a New Class of Soft X-Ray Light Sources" was held in Berkeley in October 2007. From an analysisof the most compelling scientific questions that could be identified and the experimental requirements for answering them, we set out to define, without regard to the specific technologies upon which they might be based, the capabilities such light sources would have to deliver in …
Date: September 24, 2008
Creator: Arenholz, Elke; Belkacem, Ali; Cocke, Lew; Corlett, John; Falcone, Roger; Fischer, Peter et al.
System: The UNT Digital Library
Analysis of the carbon-related 'blue' luminescence in GaN (open access)

Analysis of the carbon-related 'blue' luminescence in GaN

The properties of a broad 2.86 eV photoluminescence band in carbon-doped GaN were studied as a function of C-doping level, temperature, and excitation density. The results are consistent with a C{sub Ga}-C{sub N} deep donor-deep acceptor recombination mechanism as proposed by Seager et al. For GaN:C grown by molecular-beam epitaxy (MBE) the 2.86 eV band is observed in Si co-doped layers exhibiting high n-type conductivity as well as in semi-insulating material. For low excitation density (4 W/cm{sup 2}) the 2.86 eV band intensity decreases as a function of cw-laser exposure time over a period of many minutes. The transient behavior is consistent with a model based on carrier diffusion and charge trapping-induced Coulomb barriers. The temperature dependence of the blue luminescence below 150 K was different for carbon-contaminated GaN grown by metalorganic vapor phase epitaxy (MOVPE) compared to C-doped MBE GaN.
Date: September 24, 2004
Creator: Armitage, R.; Yang, Q. & Weber, E.R.
System: The UNT Digital Library
How well do we know the electromagnetic form factors of the proton? (open access)

How well do we know the electromagnetic form factors of the proton?

Recent measurements of recoil polarization in elastic scattering have been used to extract the ratio of the electric to the magnetic proton form factors. These results disagree with Rosenbluth extractions from cross section measurements, indicating either an inconsistency between the two techniques, or a problem with either the polarization transfer or cross section measurements. To obtain precise knowledge of the proton form factors, they must first understand the source of this discrepancy.
Date: September 24, 2002
Creator: Arrington, J.
System: The UNT Digital Library
Shielding Design Aspects of SR Beamlines for 3-GeV And 8-GeV Class Synchrotron Radiation Facilities (open access)

Shielding Design Aspects of SR Beamlines for 3-GeV And 8-GeV Class Synchrotron Radiation Facilities

Differences in synchrotron radiation beamline shielding design between the facilities of 3 GeV class and 8 GeV class are discussed with regard to SLAC SSRL and SPring-8 beamlines. Requirements of beamline shielding as well as the accelerator shielding depend on the stored electron energy, and here some factors in beamline shielding depending on the stored energy in particular, are clarified, namely the effect of build up, the effect of double scattering of photons at branch beamlines, and the spread of gas bremsstrahlung.
Date: September 24, 2007
Creator: Asano, Yoshihiro; Liu, James C. & Rokni, Sayed
System: The UNT Digital Library
Numerical methods for boundary value problems in differential-algebraic equations (open access)

Numerical methods for boundary value problems in differential-algebraic equations

Differential-algebraic equation (DAE) boundary value problems arise in a variety of applications, including optimal control and parameter estimation for constrained systems. In this paper we survey these applications and explore some of the difficulties associated with solving the resulting DAE systems. For finite difference methods, the need to maintain stability in the differential part of the system often necessitates the use of methods based on symmetric discretizations. However, these methods can suffer from instability and loss of accuracy when applied to certain DAE systems. We describe a new class of methods, Projected Implicit Runge-Kutta Methods, which overcomes these difficulties. We give convergence and stability results, and present numerical experiments which illustrate the effectiveness of the new methods. 20 refs., 1 tab.
Date: September 24, 1990
Creator: Ascher, U.M. (British Columbia Univ., Vancouver, BC (Canada). Dept. of Computer Science) & Petzold, L.R. (Lawrence Livermore National Lab., CA (USA))
System: The UNT Digital Library
Search for CP Violation in the Decays D0 to K- K+and D0 to pi- pi+ (open access)

Search for CP Violation in the Decays D0 to K- K+and D0 to pi- pi+

We measure CP-violating asymmetries of neutral charmed mesons in the modes D{sup 0} {yields} K{sup -}K{sup +} and D{sup 0} {yields} {pi}{sup -}{pi}{sup +} with the highest precision to date by using D{sup 0} {yields} K{sup -}{pi}{sup +} decays to correct detector asymmetries. An analysis of 385.8 fb{sup -}1 of data collected with the BaBar detector yields values of a{sup KK}{sub CP} = (0.00 {+-} 0.34 (stat.) {+-} 0.13 (syst.))% and a{sup {pi}{pi}}{sub CP} = (-0.24 {+-} 0.52 (stat.) {+-} 0.22 (syst.))%, which agree with Standard Model predictions.
Date: September 24, 2007
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
System: The UNT Digital Library
Challenges in the Packaging of MEMS (open access)

Challenges in the Packaging of MEMS

Microelectromechanical Systems (MEMS) packaging is much different from conventional integrated circuit (IC) packaging. Many MEMS devices must interface to the environment in order to perform their intended function, and the package must be able to facilitate access with the environment while protecting the device. The package must also not interfere with or impede the operation of the MEMS device. The die attachment material should be low stress, and low outgassing, while also minimizing stress relaxation overtime which can lead to scale factor shifts in sensor devices. The fabrication processes used in creating the devices must be compatible with each other, and not result in damage to the devices. Many devices are application specific requiring custom packages that are not commercially available. Devices may also need media compatible packages that can protect the devices from harsh environments in which the MEMS device may operate. Techniques are being developed to handle, process, and package the devices such that high yields of functional packaged parts will result. Currently, many of the processing steps are potentially harmful to MEMS devices and negatively affect yield. It is the objective of this paper to review and discuss packaging challenges that exist for MEMS systems and to …
Date: September 24, 1999
Creator: BROWN, WILLIAM D.; EATON, WILLIAM P.; MALSHE, AJAY P.; MILLER, WILLIAM M.; O'NEAL, CHAD & SINGH, SUSHILA B.
System: The UNT Digital Library
Integration of Multiple Contractors with Performance Type of Contracts (open access)

Integration of Multiple Contractors with Performance Type of Contracts

The management practices, procedures, and processes that are suited to managing Management and Operation (M&O) type of contracts at Department of Energy (DOE) sites, which were cost reimbursement with award fee, are not well suited to managing contracts where fee is determined by performance metrics. Thus a different style of management, requiring substantial revamping of the management process, is needed. This shift in philosophy also requires a dramatic shift in culture. This paper will describe how these changes are being managed at the River Protection Project (RPP), located at the DOE's Hanford Site in Washington State, one of DOE's largest and highest risk environmental clean-up project.
Date: September 24, 2000
Creator: BURDGE, L.F.
System: The UNT Digital Library
A Camera for Coherent Diffractive Imaging and Holography With a Soft-X-Ray Free Electron Laser (open access)

A Camera for Coherent Diffractive Imaging and Holography With a Soft-X-Ray Free Electron Laser

We describe a camera to record coherent scattering patterns with a soft-X-ray free-electron laser. The camera consists of a laterally-graded multilayer mirror which reflects the diffraction pattern onto a CCD detector. The mirror acts as a bandpass filter both for wavelength and angle, which isolates the desired scattering pattern from non-sample scattering or incoherent emission from the sample. The mirror also solves the particular problem of the extreme intensity of the FEL pulses, which are focused to greater than 10{sup 14} W/cm{sup 2}. The strong undiffracted pulse passes through a hole in the mirror and propagates on to a beam dump at a distance behind the instrument rather than interacting with a beamstop placed near the CCD. The camera concept is extendable for the full range of the fundamental wavelength of the FLASH FEL (i.e. between 6 nm and 60 nm) and into the water window. We have fabricated and tested various multilayer mirrors for wavelengths of 32 nm, 16 nm, 13.5 nm, and 4.5 nm. At the shorter wavelengths mirror roughness must be minimized to reduce scattering from the mirror. We have recorded over 30,000 diffraction patterns at the FLASH free-electron laser with no observable mirror damage or degradation …
Date: September 24, 2007
Creator: Bajt, S.; Chapman, H. N.; Spiller, E.; Alameda, J.; Woods, B.; Frank, M. et al.
System: The UNT Digital Library
Measurements of Coherent Synchrotron Radiation and its Impact on the LCLS Electron Beam (open access)

Measurements of Coherent Synchrotron Radiation and its Impact on the LCLS Electron Beam

In order to reach the high peak current required for an x-ray FEL, two separate magnetic dipole chicanes are used in the LCLS accelerator to compress the electron bunch length in stages. In these bunch compressors, coherent synchrotron radiation (CSR) can be emitted-induced either by a short electron bunch, or by any longitudinal density modulation that may be on the bunch. We present measurements, simulations, and analysis of (1) the CSR-induced energy loss, (2) the related transverse emittance growth, and (3) the microbunching-induced CSR directly observed at optical wavelengths.
Date: September 24, 2008
Creator: Bane, K. L. F.; Decker, F. J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J. et al.
System: The UNT Digital Library
Testing and diagnostic capabilities at LLNL (open access)

Testing and diagnostic capabilities at LLNL

Testing activities today at LLNL occur at three different locations: Livermore, Site 300, and the Nevada Test Site. At the Livermore location, there are three gas guns, two of which are used primarily for materials studies and scientific experiments on materials. The third gun is located in the High Explosive Applications Facility (HEAF) and fires into a chamber rated for 10 kg of explosive containment. The HEAF gun is used primarily for impact studies on explosives. Also within HEAF are five other containment chambers for explosive testing. Each is instrumented to varying degrees to supply the necessary information of explosive behavior. These include high speed optics, Fabry Perot velocimetry and radiography. The descriptions of the three gas guns and a summary of the HEAF facility are presented in the accompanying figures.
Date: September 24, 1998
Creator: Baum, D W
System: The UNT Digital Library
Frequency Conversion Activation on the Mercury Laser (open access)

Frequency Conversion Activation on the Mercury Laser

High efficiency frequency conversion while operating at average power is critical for the Mercury laser. We will demonstrate average power frequency conversion of face-cooled DKDP and YCOB crystals using a sapphire heat spreader approach.
Date: September 24, 2004
Creator: Bayramian, A. J.; Beach, R. J.; Bibeau, C.; Campbell, R.; Ebbers, C. A.; Freitas, B. L. et al.
System: The UNT Digital Library
Applications of Crystal Plasticity in Multiscale Modeling (open access)

Applications of Crystal Plasticity in Multiscale Modeling

Multiscale modeling with crystal plasticity constitutive relations is used to determine the average response of a polycrystal. The measured crystallographic texture of a copper shaped charge liner is used in a crystal plasticity model to construct a yield surface that exhibits normal-shear coupling. Simulations with this yield surface model demonstrate the spinning behavior observed in the spin formed copper shaped charges.
Date: September 24, 2001
Creator: Becker, R.; Busche, M.; Schwartz, A. J. & Kumar, M.
System: The UNT Digital Library
Autonomous system for pathogen detection and identification (open access)

Autonomous system for pathogen detection and identification

This purpose of this project is to build a prototype instrument that will, running unattended, detect, identify, and quantify BW agents. In order to accomplish this, we have chosen to start with the world� s leading, proven, assays for pathogens: surface-molecular recognition assays, such as antibody-based assays, implemented on a high-performance, identification (ID)-capable flow cytometer, and the polymerase chain reaction (PCR) for nucleic-acid based assays. With these assays, we must integrate the capability to: l collect samples from aerosols, water, or surfaces; l perform sample preparation prior to the assays; l incubate the prepared samples, if necessary, for a period of time; l transport the prepared, incubated samples to the assays; l perform the assays; l interpret and report the results of the assays. Issues such as reliability, sensitivity and accuracy, quantity of consumables, maintenance schedule, etc. must be addressed satisfactorily to the end user. The highest possible sensitivity and specificity of the assay must be combined with no false alarms. Today, we have assays that can, in under 30 minutes, detect and identify simulants for BW agents at concentrations of a few hundred colony-forming units per ml of solution. If the bio-aerosol sampler of this system collects 1000 Ymin …
Date: September 24, 1998
Creator: Belgrader, P.; Benett, W.; Langlois, R.; Long, G.; Mariella, R.; Milanovich, F. et al.
System: The UNT Digital Library
Group velocity delay spectroscopy technique for industrial monitoring of electron beam induced vapors (open access)

Group velocity delay spectroscopy technique for industrial monitoring of electron beam induced vapors

Spectroscopic techniques are ideal for characterization and process control of electron beam generated vapor plumes. Absorption based techniques work well for a wide variety of applications, but are difficult to apply to optically dense or opaque vapor plumes. We describe an approach for monitoring optically dense vapor plumes that is based on measuring the group velocity delay of a laser beam near an optical transition to determine the vapor density. This technique has a larger dynamic range than absorption spectroscopy. We describe our progress towards a robust system to monitor aluminum vaporization in an industrial environment. Aluminum was chosen because of its prevalence in high performance aircraft alloys. In these applications, composition control of the alloy constituents is critical to the deposition process. Data is presented demonstrating the superior dynamic range of the measurement. In addition, preliminary data demonstrating aluminum vapor rate control in an electron beam evaporator is presented. Alternative applications where this technique could be useful are discussed. Keywords: Group velocity delay spectroscopy, optical beat signal, optical heterodyne, index of refraction, laser absorption spectroscopy, external cavity diode laser (ECDL), electron beam vaporization, vapor density, vapor phase manufacturing, process control
Date: September 24, 1998
Creator: Benterou, J J; Berzins, L V & Sharma, M N
System: The UNT Digital Library
Bounds and Estimates for Transport Coefficients of Random and Porous Media with High Contrasts (open access)

Bounds and Estimates for Transport Coefficients of Random and Porous Media with High Contrasts

Bounds on transport coefficients of random polycrystals of laminates are presented, including the well-known Hashin-Shtrikman bounds and some newly formulated bounds involving two formation factors for a two-component porous medium. Some new types of self-consistent estimates are then formulated based on the observed analytical structure both of these bounds and also of earlier self-consistent estimates (of the CPA or coherent potential approximation type). A numerical study is made, assuming first that the internal structure (i.e., the laminated grain structure) is not known, and then that it is known. The purpose of this aspect of the study is to attempt to quantify the differences in the predictions of properties of a system being modeled when such organized internal structure is present in the medium but detailed spatial correlation information may or (more commonly) may not be available. Some methods of estimating formation factors from data are also presented and then applied to a high-contrast fluid-permeability data set. Hashin-Shtrikman bounds are found to be very accurate estimates for low contrast heterogeneous media. But formation factor lower bounds are superior estimates for high contrast situations. The new self-consistent estimators also tend to agree better with data than either the bounds or the CPA …
Date: September 24, 2004
Creator: Berger, E. L.
System: The UNT Digital Library
Research and Development for X-Ray Optics and Diagnostics on the Linac Coherent Source (LCLS) (open access)

Research and Development for X-Ray Optics and Diagnostics on the Linac Coherent Source (LCLS)

The Linac Coherent Light Source (LCLS) is a 1.5 to 15 {angstrom} wavelength Free-Electron Laser (PEL), under development at the Stanford Linear Accelerator Center (SLAC). The photon output consists of high brightness, transversely coherent pulses with duration < 300 fs, together with a broad spontaneous spectrum. The output energy density per unit area, pulse duration, repetition rate, and small FEL spot size pose special challenges for optical components and diagnostics downstream of the undulator. Planning for the photon beam transport, manipulation and diagnostics downstream of the undulator has begun.
Date: September 24, 2002
Creator: Bionta, R. M.; Arthur, J.; Chapman, H.; Craig, B.; Klingmann, J.; Kuba, J. et al.
System: The UNT Digital Library
Geothermal Symposium: Low-Temperature Utilization, Heat-Pump Applications, District Heating (open access)

Geothermal Symposium: Low-Temperature Utilization, Heat-Pump Applications, District Heating

Separate abstracts are prepared for twelve papers presented at the symposium. (MCW)
Date: September 24, 1980
Creator: Bloomquist, R. G.
System: The UNT Digital Library
Experimental investigation of high mach number 3D hydrodynamic jets at the National Ignition Facility (open access)

Experimental investigation of high mach number 3D hydrodynamic jets at the National Ignition Facility

The first hydrodynamics experiments were performed on the National Ignition Facility. A supersonic jet was formed via the interaction of a laser driven shock ({approx}40 Mbars) with 2D and 3D density perturbations. The temporal evolution of the jet's spatial scales and ejected mass were measured with point projection x-ray radiography. Measurements of the large-scale features and mass are in good agreement with 2D and 3D numerical simulations. These experiments are the first quantitative measurements of the evolution of 3D supersonic jets and provide insight into their 3D behavior.
Date: September 24, 2004
Creator: Blue, B. E.; Weber, S.; Glendinning, S.; Lanier, N.; Woods, D.; Bono, M. et al.
System: The UNT Digital Library
Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator (open access)

Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator

Recent experiments at SLAC have shown that high gradient acceleration of electrons is achievable in meter scale plasmas. Results from these experiments show that the wakefield is sensitive to parameters in the electron beam which drives it. In the experiment the bunch lengths were varied systematically at constant charge. The effort to extract a measurement of the decelerating wake from the maximum energy loss of the electron beam is discussed.
Date: September 24, 2008
Creator: Blumenfeld, I.; Clayton, C. E.; Decker, F. J.; Hogan, M. J.; Huang, C.; Ischebeck, R. et al.
System: The UNT Digital Library
A Review of Wind Project Financing Structures in the USA (open access)

A Review of Wind Project Financing Structures in the USA

The rapid pace of wind power development in the U.S. over the last decade has outstripped the ability of most project developers to provide adequate equity capital and make efficient use of project-related tax benefits. In response, the sector has created novel project financing structures that feature varying combinations of equity capital from project developers and third-party tax-oriented investors, and in some cases commercial debt. While their origins stem from variations in the financial capacity and business objectives of wind project developers, as well as the risk tolerances and objectives of equity and debt providers, each structure is, at its core, designed to manage project risk and allocate federal tax incentives to those entities that can use them most efficiently. This article surveys the six principal financing structures through which most new utility-scale wind projects (excluding utility-owned projects) in the U.S. have been financed from 1999 to the present. These structures include simple balance-sheet finance, several varieties of all-equity special allocation partnership 'flip' structures, and two leveraged structures. In addition to describing each structure's mechanics, the article also discusses its rationale for use, the types of investors that find it appealing and why, and its relative frequency of use in …
Date: September 24, 2008
Creator: Bolinger, Mark A.; Harper, John & Karcher, Matthew
System: The UNT Digital Library