Direct Comparison of Brookhaven Reflectivity Measurements with Free-Electron Theory (open access)

Direct Comparison of Brookhaven Reflectivity Measurements with Free-Electron Theory

The reflectivity at normal incidence of copper and aluminum samples was recently measured over a large frequency range at Brookhaven by one of us (JT). Then using the Kramers-Kroning integrals, and assuming the free-electron model of conductivity, the dependence of conductivity on frequency was obtained. The results seemed to suggest, for example, that the dc conductivities of the copper and evaporated aluminum samples are a factor of 3 lower than expected. We propose in this report, instead, directly fitting the free-electron model to the low frequency end of the reflectivity data. This fitting does not depend on the higher frequency results and on Kramers-Kronig integrations, but it does assume that the data at the low frequency end is sufficiently accurate. Note that for our LCLS wakefield studies, it is only over these (relatively) low frequencies that we need to know the electrical properties of the metals. The equations that relate reflectivity R with the free electron parameters dc conductivity {sigma} and relaxation time {tau} are: (1) {tilde {sigma}} = {sigma}/1-ikc{tau}; (2) {tilde n} = {radical} {tilde {epsilon}} = {radical}(1+4{pi}i{tilde k}c/{omega}); and (3) R = |{tilde n}-1/{tilde n} + 1|{sup 2}. The parameters are ac conductivity {tilde {sigma}}, index of refraction …
Date: December 13, 2010
Creator: Bane, Karl L.F.
System: The UNT Digital Library
LITERATURE REVIEW ON MAXIMUM LOADING OF RADIONUCLIDES ON CRYSTALLINE SILICOTITANATE (open access)

LITERATURE REVIEW ON MAXIMUM LOADING OF RADIONUCLIDES ON CRYSTALLINE SILICOTITANATE

Plans are underway to use small column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions at Savannah River Site. The ion exchange material slated for the SCIX project is engineered or granular crystalline silicotitanate (CST). Information on the maximum loading of radionuclides on CST is needed by Savannah River Remediation for safety evaluations. A literature review has been conducted that culminated in the estimation of the maximum loading of all but one of the radionuclides of interest (Cs-137, Sr-90, Ba-137m, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, and Cm-244). No data was found for Cm-244.
Date: October 13, 2010
Creator: Adu-Wusu, K. & Pennebaker, F.
System: The UNT Digital Library
A Design Report for the Optical Transition Radiation Imager for the LCLS Undulator (open access)

A Design Report for the Optical Transition Radiation Imager for the LCLS Undulator

The Linac Coherent Light Source (LCLS), a free-electron x-ray laser, is under design and construction. Its high-intensity electron beam, 3400 A in peak current and 46 TW in peak power, is concentrated in a small area (37 micrometer in rms radius) inside its undulator. Ten optical transition radiation (OTR) imagers are planned between the undulator segments for characterizing the transverse profiles of the electron beam. In this note, we report on the optical and mechanical design of the OTR imager. Through a unique optical arrangement, using a near-normal-incidence screen and a multi-layer coated mirror, this imager will achieve a fine resolution (12 micrometer or better) over the entire field of view (8 mm x 5 mm), with a high efficiency for single-shot imaging. A digital camera will be used to read out the beam images in a programmable region (5 mm x 0.5 mm) at the full beam repetition rate (120 Hz), or over the entire field at a lower rate (10 Hz). Its built-in programmable amplifier will be used as an electronic intensity control.
Date: December 13, 2010
Creator: Yang, Bingxin
System: The UNT Digital Library
Development of a Polar Drive Shock Ignition Platform on the National Ignition Facility (open access)

Development of a Polar Drive Shock Ignition Platform on the National Ignition Facility

None
Date: May 13, 2010
Creator: Perkins, L. J.; Schurtz, G. P.; Betti, R.; Craxton, R. S.; LaFortune, K. N.; Casner, A. et al.
System: The UNT Digital Library
Effects of Electromagnetic Fields on Fish and Invertebrates (open access)

Effects of Electromagnetic Fields on Fish and Invertebrates

In this progress report, we describe the preliminary experiments conducted with three fish and one invertebrate species to determine the effects of exposure to electromagnetic fields. During fiscal year 2010, experiments were conducted with coho salmon (Onchrohychus kisutch), California halibut (Paralicthys californicus), Atlantic halibut (Hippoglossus hippoglossus), and Dungeness crab (Cancer magister). The work described supports Task 2.1.3: Effects on Aquatic Organisms, Subtask 2.1.3.1: Electromagnetic Fields.
Date: October 13, 2010
Creator: Schultz, Irvin R.; Woodruff, Dana L.; Marshall, Kathryn E.; Pratt, William J. & Roesijadi, Guritno
System: The UNT Digital Library
Safeguard By Design Lessons Learned from DOE Experience Integrating Safety into Design (open access)

Safeguard By Design Lessons Learned from DOE Experience Integrating Safety into Design

This paper identifies the lessons to be learned for the institutionalization of Safeguards by Design (SBD) from the Department of Energy (DOE) experience developing and implementing DOE-STD-1189-2008, Integration of Safety into the Design Process. The experience is valuable because of the similarity of the challenges of integrating safety and safeguards into the design process. The paper reviews the content and development of DOE-STD-1189-2008 from its initial concept in January 2006 to its issuance in March 2008. Lessons learned are identified in the areas of the development and structure of requirements for the SBD process; the target audience for SBD requirements and guidance, the need for a graded approach to SBD, and a possible strategy for development and implementation of SBD within DOE.
Date: April 13, 2010
Creator: Hockert, John & Burbank, Roberta L.
System: The UNT Digital Library
A Vibrating Wire System For Quadrupole Fiducialization (open access)

A Vibrating Wire System For Quadrupole Fiducialization

A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire …
Date: December 13, 2010
Creator: Wolf, Zachary
System: The UNT Digital Library
Efficiency Improvement of Nitride-Based Solid State Light Emitting Materials -- CRADA Final Report (open access)

Efficiency Improvement of Nitride-Based Solid State Light Emitting Materials -- CRADA Final Report

The development of In{sub x}Ga{sub 1-x} N/GaN thin film growth by Molecular Beam Epitaxy has opened a new route towards energy efficient solid-state lighting. Blue and green LED's became available that can be used to match the whole color spectrum of visible light with the potential to match the eye response curve. Moreover, the efficiency of such devices largely exceeds that of incandescent light sources (tungsten filaments) and even competes favorably with lighting by fluorescent lamps. It is, however, also seen in Figure 1 that it is essential to improve on the luminous performance of green LED's in order to mimic the eye response curve. This lack of sufficiently efficient green LED's relates to particularities of the In{sub x}Ga{sub 1-x}N materials system. This ternary alloy system is polar and large strain is generated during a lattice mismatched thin film growth because of the significantly different lattice parameters between GaN and InN and common substrates such as sapphire. Moreover, it is challenging to incorporate indium into GaN at typical growth temperatures because a miscibility gap exists that can be modified by strain effects. As a result a large parameter space needs exploration to optimize the growth of In{sub x}Ga{sub 1-x}N and …
Date: May 13, 2010
Creator: Kisielowski, Christian & Weber, Eicke
System: The UNT Digital Library
Effect of Asymmetric Versus Symmetric Warming on Grassland Mesocosms: Final Report (open access)

Effect of Asymmetric Versus Symmetric Warming on Grassland Mesocosms: Final Report

Final Report for “Effect of Asymmetric Versus Symmetric Warming on Grassland Mesocosms”
Date: December 13, 2010
Creator: Olszyk, David M.
System: The UNT Digital Library
Realizing novel accelerator concepts in an X-band photo-injector (open access)

Realizing novel accelerator concepts in an X-band photo-injector

In this project we propose to investigate the use of novel accelerator structure cell geometry to enhance the performance of X-band photo-injectors. Making novel accelerator concepts possible involves fabrication and testing of components to ensure that the performance predicted by simulation is robustly achievable. This work is important because photo-injectors are increasingly used to provide high brightness electron beams for light sources, pushing their performance to the limits, but also requiring them to be user-facility stable. Careful investigation in both computer simulation and design, and low power testing of piece parts will enable the successful fabrication of an advanced X-band photo-injector.
Date: April 13, 2010
Creator: Marsh, R
System: The UNT Digital Library
Triggering for Magnetic Field Measurements of the LCLS Undulators (open access)

Triggering for Magnetic Field Measurements of the LCLS Undulators

A triggering system for magnetic field measurements of the LCLS undulators has been built with a National Instruments PXI-1002 and a Xylinx FPGA board. The system generates single triggers at specified positions, regardless of encoder sensor jitter about a linear scale.
Date: December 13, 2010
Creator: Hacker, Kirsten
System: The UNT Digital Library
Location of Maximum Credible Beam Losses in LCLS Injector (open access)

Location of Maximum Credible Beam Losses in LCLS Injector

The memo describes the maximum credible beam the LCLS injector can produce and lose at various locations along the beamline. The estimation procedure is based upon three previous reports [1, 2, 3]. While specific numbers have been updated to accurately reflect the present design parameters, the conclusions are very similar to those given in Ref 1. The source of the maximum credible beam results from the explosive electron emission from the photocathode if the drive laser intensity exceeds the threshold for plasma production. In this event, the gun's RF field can extract a large number of electrons from this plasma which are accelerated out of the gun and into the beamline. This electron emission persists until it has depleted the gun of all its energy. Hence the number of electrons emitted per pulse is limited by the amount of stored RF energy in the gun. It needs to be emphasized that this type of emission is highly undesirable, as it causes permanent damage to the cathode.
Date: December 13, 2010
Creator: Mao, Stan
System: The UNT Digital Library
Potentially Missing Physics of the Early Universe: Nonlinear Vacuum Polarization in Intense Blackbody Radiation (open access)

Potentially Missing Physics of the Early Universe: Nonlinear Vacuum Polarization in Intense Blackbody Radiation

The standard Big Bang universe model is mainly based on linear interactions, except during exotic periods such as inflation. The purpose of the present proposal is to explore the effects, if any, of vacuum polarization in the very high energy density environment of the early universe. These conditions can be found today in astrophysical settings and may also be emulated in the laboratory using high intensity advanced lasers. Shortly after the Big Bang, there once existed a time when the energy density of the universe corresponded to a temperature in the range 10{sup 8} - 10{sup 9} K, sufficient to cause vacuum polarization effects. During this period, the nonlinear vacuum polarization may have had significant modifications on the propagation of radiation. Thus the thermal spectrum of the early universe may have been starkly non-Planckian. Measurements of the cosmic microwave background today show a spectrum relatively close to an ideal blackbody. Could the early universe have shown spectral deviations due to nonlinear vacuum effects? If so, is it possible to detect traces of those relic photons in the universe today? Found in galactic environments, compact objects such as blazars and magnetars can possess astronomically large energy densities that far exceed anything …
Date: April 13, 2010
Creator: Wu, S Q & Hartemann, F V
System: The UNT Digital Library
Earth's Magnetic Field Measurements for the LCLS Undulators (open access)

Earth's Magnetic Field Measurements for the LCLS Undulators

Measurements of the earth's magnetic field at several locations at SLAC were conducted to determine the possible field error contribution from tuning the undulators in a location with a different magnetic field than that which will be found in the undulator hall. An average difference of 0.08 {+-} 0.04 Gauss has been measured between the downward earth's field components in the test facility and SLAC tunnel locations.
Date: December 13, 2010
Creator: Hacker, Kirsten
System: The UNT Digital Library
Wakefield Computations for the Injector (Part I) (open access)

Wakefield Computations for the Injector (Part I)

In this document, we report on basic wakefield computations used to establish the impedance budget for the LCLS injector. Systematic comparisons between analytic formulae and results from ABCI are done. Finally, a comparison between 2D and 3D wakefield calculations are given for a cross. The three parts of the document are presented as follows: (1) ABCI computations for a few structures (Flange, Bellows...); (2) Comparison analytic with ABCI runs; and (3) Comparison Cross and Cavity using MAFIA.
Date: December 13, 2010
Creator: Limborg-Deprey, C.
System: The UNT Digital Library
Assessment of the Building 3430 Filtered Exhaust Stack Sampling Probe Location (open access)

Assessment of the Building 3430 Filtered Exhaust Stack Sampling Probe Location

Pacific Northwest National Laboratory performed a demonstration to determine the acceptable location in which to place an air sampling probe for emissions monitoring for radionuclides in the exhaust air discharge from the new 3430 Building Filtered Pathway Stack . The method was to adopt the results of a previously performed test series for a system of similar configuration, followed by a partial test on the actual system to verify the applicability of previously performed tests. The qualification criteria included 1) a uniform air velocity, 2) an average flow angle that does not deviate from the axis of the duct by more than 20°, 3) a uniform concentration of tracer gases, and 4) a uniform concentration of tracer particles. Section 1 provides background information for the demonstration, and Section 2 describes the test strategy, including the criteria for the applicability of model results and the test matrix. Section 3 describes the flow angle test and the velocity uniformity test, Section 4 provides the test results, and Section 5 provides the conclusions. Appendix A includes the test data sheets, and Appendix B gives applicable qualification results from the previously tested model stack. The data from the previously tested and similarly designed stack …
Date: April 13, 2010
Creator: Glissmeyer, John A.
System: The UNT Digital Library
SALTSTONE 3QCY09 TCLP RESULTS (open access)

SALTSTONE 3QCY09 TCLP RESULTS

A Saltstone waste form was prepared in the Savannah River National Laboratory (SRNL) from a Tank 50H sample and Z-Area premix material for the third quarter of calendar year 2009 (3QCY09). After the prescribed 28 day cure, samples of the saltstone were collected, and the waste form was shown to meet the South Carolina Hazardous Waste Management Regulations (SCHWMR) R.61-79.261.24 and R.61-79.268.48(a) requirements for a nonhazardous waste form with respect to RCRA metals and underlying hazardous constituents. These analyses met all quality assurance specifications of USEPA SW-846. The Saltstone Production Facility (SPF) receives waste from Tank 50H for treatment. In the third quarter of the 2009 calendar year (3QCY09), Tank 50H accepted transfers of approximately 37 kgal from the Effluent Treatment Project (ETP) waste, approximately 5 kgal from Tank 710 - the H-Canyon General Purpose Evaporator, approximately 26 kgal from Tank 221H, approximately 319 kgal from the Modular Caustic Side Solvent Extraction Unit (MCU) Decontaminated Salt Solution Hold Tank (DSS-HT), and approximately 358 kgal from Tank 23H. The Saltstone Grout Sampling plan provides the South Carolina Department of Health and Environmental Control (SCDHEC) with the chemical and physical characterization strategy for the salt solution which is to be disposed of …
Date: January 13, 2010
Creator: Reigel, M.
System: The UNT Digital Library
FREIGHT CONTAINER LIFTING STANDARD (open access)

FREIGHT CONTAINER LIFTING STANDARD

This standard details the correct methods of lifting and handling Series 1 freight containers following ISO-3874 and ISO-1496. The changes within RPP-40736 will allow better reading comprehension, as well as correcting editorial errors.
Date: January 13, 2010
Creator: DJ, POWERS; MA, SCOTT & TC, MACKEY
System: The UNT Digital Library
FRIT DEVELOPMENT FOR SLUDGE BATCH 6 (open access)

FRIT DEVELOPMENT FOR SLUDGE BATCH 6

The Savannah River National Laboratory (SRNL) evaluated a large number of Sludge Batch 6 (SB6) composition projections to support frit optimization for SB6 vitrification at the Defense Waste Processing Facility (DWPF). The evaluations discussed in this report occurred over a period of about 4 months, and included about 40 composition projections, developed by both Savannah River Remediation (SRR) and SRNL. Paper study assessments were used to evaluate the sludge composition projections with arrays of potential frit compositions using the predictive models in the DWPF Product Composition Control System (PCCS). Both nominal sludge compositions and sludge compositions with anticipated compositional variation were considered. The model predictions were used to identify candidate frit compositions for each SB6 projection and to provide some guidance to SRR on washing and blending strategies for SB6 preparation. This report presents a chronological review of this process and summarizes the findings at each stage. Following initial feedback from this work, the number of washes in Tank 51 was reduced to increase the projected sodium concentration in SB6. Analyses of predicted frit performance before and after a potential decant of Tank 40 showed that the post-decant SB6 composition would be difficult to process with any frit composition and …
Date: May 13, 2010
Creator: Fox, K.; Edwards, T. & Zamecnik, J.
System: The UNT Digital Library
Studies in Low-Energy Nuclear Science (open access)

Studies in Low-Energy Nuclear Science

This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between March 1, 2006 and October 31, 2009 which were supported by U.S. DOE grant number DE-FG52-06NA26187.
Date: January 13, 2010
Creator: Brune, Carl R. & Grimes, Steven M.
System: The UNT Digital Library
Tracking the Sun III; The Installed Cost of Photovoltaics in the United States from 1998-2009 (open access)

Tracking the Sun III; The Installed Cost of Photovoltaics in the United States from 1998-2009

Installations of solar photovoltaic (PV) systems have been growing at a rapid pace in recent years. In 2009, approximately 7,500 megawatts (MW) of PV were installed globally, up from approximately 6,000 MW in 2008, consisting primarily of grid-connected applications. With 335 MW of grid-connected PV capacity added in 2009, the United States was the world's fourth largest PV market in 2009, behind Germany, Italy, and Japan. The market for PV in the United States is driven by national, state, and local government incentives, including up-front cash rebates, production-based incentives, requirements that electricity suppliers purchase a certain amount of solar energy, and federal and state tax benefits. These programs are, in part, motivated by the popular appeal of solar energy, and by the positive attributes of PV - modest environmental impacts, avoidance of fuel price risks, coincidence with peak electrical demand, and the possible deployment of PV at the point of use. Given the relatively high cost of PV, however, a key goal of these policies is to encourage cost reductions over time. Therefore, as policy incentives have become more significant and as PV deployment has accelerated, so too has the desire to track the installed cost of PV systems over …
Date: December 13, 2010
Creator: Barbose, Galen; Darghouth, Naim & Wiser, Ryan
System: The UNT Digital Library
Aerodynamic Design Criteria for Class 8 Heavy Vehicles Trailer Base Devices to Attain Optimum Performance (open access)

Aerodynamic Design Criteria for Class 8 Heavy Vehicles Trailer Base Devices to Attain Optimum Performance

Lawrence Livermore National Laboratory (LLNL) as part of its Department of Energy (DOE), Energy Efficiency and Renewable Energy (EERE), and Vehicle Technologies Program (VTP) effort has investigated class 8 tractor-trailer aerodynamics for many years. This effort has identified many drag producing flow structures around the heavy vehicles and also has designed and tested many new active and passive drag reduction techniques and concepts for significant on the road fuel economy improvements. As part of this effort a database of experimental, computational, and conceptual design for aerodynamic drag reduction devices has been established. The objective of this report is to provide design guidance for trailer base devices to improve their aerodynamic performance. These devices are commonly referred to as boattails, base flaps, tail devices, and etc. The information provided here is based on past research and our most recent full-scale experimental investigations in collaboration with Navistar Inc. Additional supporting data from LLNL/Navistar wind tunnel, track test, and on the road test will be published soon. The trailer base devices can be identified by 4 flat panels that are attached to the rear edges of the trailer base to form a closed cavity. These devices have been engineered in many different forms …
Date: December 13, 2010
Creator: Salari, K & Ortega, J
System: The UNT Digital Library
Innovations in Nuclear Infrastructure and Education (open access)

Innovations in Nuclear Infrastructure and Education

The decision to implement the Innovation in Nuclear Infrastructure and Engineering Program (INIE) was an important first step towards ensuring that the United States preserves its worldwide leadership role in the field of nuclear science and engineering. Prior to INIE, university nuclear science and engineering programs were waning, undergraduate student enrollment was down, university research reactors were being shut down, while others faced the real possibility of closure. For too long, cutting edge research in the areas of nuclear medicine, neutron scattering, radiochemistry, and advanced materials was undervalued and therefore underfunded. The INIE program corrected this lapse in focus and direction and started the process of drawing a new blueprint with positive goals and objectives that supports existing as well the next generation of educators, students and researchers.
Date: December 13, 2010
Creator: Bernard, John
System: The UNT Digital Library
Catalog of DC Appliances and Power Systems (open access)

Catalog of DC Appliances and Power Systems

This document catalogs the characteristics of current and potential future DC products and power systems.
Date: October 13, 2010
Creator: Garbesi, Karina; Vossos, Vagelis & Shen, Hongxia
System: The UNT Digital Library