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2D-ACAR Spectra of Insulating and Superconducting Y-123: An overview of the two-dimensional angular correlation (2D-ACAR) positron annihilation results for the three fundamental phases of YBa{sub 2}Cu{sub 3}O{sub x}, namely, the normal metal, the superconductor, and the insulator, is presented. In addition to the c-axis projected momentum density, the recent results for the a-axis projection as well as the insulating Y123 are discussed. The experimental results are compared and contrasted with the corresponding band theory predictions as far as possible in order to gain insight into the electronic structure and Fermiology of this archetypal high-{Tc} superconductor.
33rd Annual Report: The ACIR Library is composed of publications that study the interactions between different levels of government. This document is an annual report.
3D-Flow Processor for a Programmable Level-1 Trigger (Feasibility Study): A feasibility study has been made to use the 3D-Flow processor in a pipelined programmable parallel processing architecture to identify particles such as electrons, jets, muons, etc., in high-energy physics experiments.
ABAREX: A neutron spherical optical-statistical model code: The spherical optical-statistical model is briefly reviewed and the capabilities of the neutron scattering code, ABAREX, are presented. Input files for ten examples, in which neutrons are scattered by various nuclei, are given and the output of each run is discussed in detail.
ABAREX: A neutron spherical optical-statistical model code: The spherical optical-statistical model is briefly reviewed and the capabilities of the neutron scattering code, ABAREX, are presented. Input files for ten examples, in which neutrons are scattered by various nuclei, are given and the output of each run is discussed in detail.
Abrasive wear by coal-fueled diesel engine and related particles: The development of commercially viable diesel engines that operate directly on pulverized coal-fuels will require solution to the problem of severe abrasive wear. The purpose of the work described in this report was to investigate the nature of the abrasive wear problem. Analytical studies were carried out to determine the characteristics of the coal-fuel and associated combustion particles responsible for abrasion. Laboratory pinon-disk wear tests were conducted on oil-particle mixtures to determine the relationship between wear rate and a number of different particle characteristics, contact parameters, specimen materials properties, and other relevant variables.
Abrasive wear by coal-fueled diesel engine and related particles: The development of commercially viable diesel engines that operate directly on pulverized coal-fuels will require solution to the problem of severe abrasive wear. The purpose of the work described in this report was to investigate the nature of the abrasive wear problem. Analytical studies were carried out to determine the characteristics of the coal-fuel and associated combustion particles responsible for abrasion. Laboratory pinon-disk wear tests were conducted on oil-particle mixtures to determine the relationship between wear rate and a number of different particle characteristics, contact parameters, specimen materials properties, and other relevant variables.
Absolute total and one and two electron transfer cross sections for Ar{sup 8+} on Ar as a function of energy: The absolute total and one and two electron transfer cross sections for Ar{sup 8+} on Ar were measured as a function of projectile laboratory energy from 0.090 to 0.550 keV/amu. The effective one electron transfer cross section dominates above 0.32 keV/amu, while below this energy, the effective two electron transfer starts to become appreciable. The total cross section varies by a factor over the energy range explored. The overall error in the cross section measurement is estimated to be {plus_minus} 15%.
Absorption of undulator radiation in media: Detailed thermal stress analyses of beamline and optical components subject to high heat loads require an Accurate determination of the absorbed power profile for accurate prediction of the temperature profile and structural parameters. This is particularly important for high power beams from wigglers and undulators at the third generation synchrotron sources because components must, in general, be designed and maintained with strict mechanical tolerances. The spatial distribution of the power density of an undulator is a rapidly varying function of the energy of the photons suggesting that approximative methods based on a smooth spectral variation may not be valid. In this paper, a fast code for calculating undulator spectra is developed and compared with a wiggler code for approximation of the same spectra. Results from numerical simulations, including the emittance of the stored particle beam, are presented for the absorbed power density in a beryllium window. We find markedly different results for the two models for far off-axis radiation indicating the inadequacy of the wiggler model applied to an undulator spectrum in this case. The wiggler model overestimates the total absorbed power by as much as 82% for the beryllium window.
Absorption of undulator radiation in media: Detailed thermal stress analyses of beamline and optical components subject to high heat loads require an Accurate determination of the absorbed power profile for accurate prediction of the temperature profile and structural parameters. This is particularly important for high power beams from wigglers and undulators at the third generation synchrotron sources because components must, in general, be designed and maintained with strict mechanical tolerances. The spatial distribution of the power density of an undulator is a rapidly varying function of the energy of the photons suggesting that approximative methods based on a smooth spectral variation may not be valid. In this paper, a fast code for calculating undulator spectra is developed and compared with a wiggler code for approximation of the same spectra. Results from numerical simulations, including the emittance of the stored particle beam, are presented for the absorbed power density in a beryllium window. We find markedly different results for the two models for far off-axis radiation indicating the inadequacy of the wiggler model applied to an undulator spectrum in this case. The wiggler model overestimates the total absorbed power by as much as 82% for the beryllium window.
Ac loss measurement of SSC dipole magnets: AC losses in full length and 1.5 m model SSC collider dipoles were successfully measured by the direct observation of energy flow into and out of magnets during a ramp cycle. The measurement was performed by using two double-integrating type digital volt meters (DVM's) for current and voltage measurement. Measurements were performed for six is m long ASST magnets and five 1.5 m long model magnets, inducting one 40 mm diameter magnet. There were large variations in the eddy current losses. Since these magnets use conductors with slight deviations in their internal structures and processing of the copper surface depending on the manufacturer, it is likely that there are differences in the contact resistance between strands. Correlation between the ramp rate dependence of the,quench current and the eddy current loss was evident.
AC Loss Measurement of SSC Dipole Magnets: AC losses in full length and 1.5 m model SSC collider dipoles were successfully measured by the direct observation of energy flow into and out of magnets during a ramp cycle. The measurement was performed by using two double-integrating type digital volt meters (DVM`s) for current and voltage measurement. Measurements were performed for six is m long ASST magnets and five 1.5 m long model magnets, inducting one 40 mm diameter magnet. There were large variations in the eddy current losses. Since these magnets use conductors with slight deviations in their internal structures and processing of the copper surface depending on the manufacturer, it is likely that there are differences in the contact resistance between strands. Correlation between the ramp rate dependence of the,quench current and the eddy current loss was evident.
AC loss measurements of model and full size 50mm SSC collider dipole magnets at Fermilab: Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500, to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar magnet types agree to within experimental error, while eddy current losses correlate strongly with the observed dependence of quench current on ramp rate.
AC loss measurements of model and full size 50mm SSC collider dipole magnets at Fermilab: Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500, to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar magnet types agree to within experimental error, while eddy current losses correlate strongly with the observed dependence of quench current on ramp rate.
Accelerated glass reaction under PCT conditions: Static leach tests similar to PCT (Product Consistency Test) were performed for up to 2 years to assess long-term reaction behavior of high-level nuclear waste glasses similar to those at Defense Waste Processing Facility. These tests show the reaction rate to decrease with the reaction time from an initially high rate to a low rate, but then to accelerate to a higher rate after reaction times of about 1 year, depending on glass surface area/leachant volume ratio used. Solution concentrations of soluble glass components increase as the reaction is accelerated, while release of other glass components into solution is controlled by secondary phases. Net result is that transformation of glass to stable phases is accelerated while the solution becomes enriched in soluble components not effectively contained in secondary phases. Rate becomes linear in time after the acceleration and may be similar to the initial forward rate. A current model of glass reaction predicts that the glass reaction will be accelerated upon the formation of secondary phases which lower the silicic acid solution concentration. These tests show total Si concentration to increase upon reaction acceleration, however, which may be due to the slightly higher pH attained with the acceleration. The sudden change in the reaction rate is likely due to secondary phase formation. 17 refs, 2 tabs, 3 figs.
Accelerated glass reaction under PCT conditions: Static leach tests similar to PCT (Product Consistency Test) were performed for up to 2 years to assess long-term reaction behavior of high-level nuclear waste glasses similar to those at Defense Waste Processing Facility. These tests show the reaction rate to decrease with the reaction time from an initially high rate to a low rate, but then to accelerate to a higher rate after reaction times of about 1 year, depending on glass surface area/leachant volume ratio used. Solution concentrations of soluble glass components increase as the reaction is accelerated, while release of other glass components into solution is controlled by secondary phases. Net result is that transformation of glass to stable phases is accelerated while the solution becomes enriched in soluble components not effectively contained in secondary phases. Rate becomes linear in time after the acceleration and may be similar to the initial forward rate. A current model of glass reaction predicts that the glass reaction will be accelerated upon the formation of secondary phases which lower the silicic acid solution concentration. These tests show total Si concentration to increase upon reaction acceleration, however, which may be due to the slightly higher pH attained with the acceleration. The sudden change in the reaction rate is likely due to secondary phase formation. 17 refs, 2 tabs, 3 figs.
Accelerated irradiation test of Gundremmingen reactor vessel trepan material: Initial mechanical properties tests of beltline trepanned from the decommissioned KRB-A pressure vessel and archive material irradiated in the UBR test reactor revealed a major anomaly in relative radiation embrittlement sensitivity. Poor correspondence of material behavior in test vs. power reactor environments was observed for the weak test orientation (ASTL C-L) whereas correspondence was good for the strong orientation (ASTM C-L). To resolve the anomaly directly, Charpy-V specimens from a low (essentially-nil) fluence region of the vessel were irradiated together with archive material at 279{degrees}C in the UBR test reactor. Properties tests before UBR irradiation revealed a significant difference in 41-J transition temperature and upper shelf energy level between the materials. However, the materials exhibited essentially the same radiation embrittlement sensitivity (both orientations), proving that the anomaly is not due to a basic difference in material irradiation resistances. Possible causes of the original anomaly and the significance to NRC Regulatory Guide 1.99 are discussed.
Accelerated radioactive nuclear beams: Existing and planned facilities: An over-view of existing and planned radioactive nuclear beam facilities world-wide. Two types of production methods are distinguished: projectile fragmentation and the on-line isotope separator (ISOL) method. While most of the projectile fragmentation facilities are already in operation, almost all the ISOL-based facilities are in still the planning stage.
Acceleration of electrons using an inverse free electron laser auto- accelerator: We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.
Acceleration of electrons using an inverse free electron laser auto- accelerator: We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW`s) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.
Accelerator and fusion research division. 1992 Summary of activities: This report contains brief discussions on research topics in the following area: Heavy-Ion Fusion Accelerator Research; Magnetic Fusion Energy; Advanced Light Source; Center for Beam Physics; Superconducting Magnets; and Bevalac Operations.
Accelerator physics analysis with an integrated toolkit: Work is in progress on an integrated software toolkit for linear and nonlinear accelerator design, analysis, and simulation. As a first application, beamline'' and MXYZPTLK'' (differential algebra) class libraries, were used with an X Windows graphics library to build an user-friendly, interactive phase space tracker which, additionally, finds periodic orbits. This program was used to analyse a theoretical lattice which contains octupoles and decapoles to find the 20th order, stable and unstable periodic orbits and to explore the local phase space structure.
Accelerator physics analysis with an integrated toolkit: Work is in progress on an integrated software toolkit for linear and nonlinear accelerator design, analysis, and simulation. As a first application, ``beamline`` and ``MXYZPTLK`` (differential algebra) class libraries, were used with an X Windows graphics library to build an user-friendly, interactive phase space tracker which, additionally, finds periodic orbits. This program was used to analyse a theoretical lattice which contains octupoles and decapoles to find the 20th order, stable and unstable periodic orbits and to explore the local phase space structure.
Accelerator physics of the Stanford Linear Collider and SLC accelerator experiments towards the Next Linear Collider: The Stanford Linear Collider (SLC) was built to collide single bunches of electrons and positrons head-on at a single interaction point with single beam energies up to 55 GeV. The small beam sizes and high currents required for high luminosity operation have significantly pushed traditional beam quality limits. The Polarized Electron Source produces about 8 {times} 10{sup 10} electrons in each of two bunches with up to 28% polarization,. The Damping Rings provide coupled invariant emittances of 1.8 {times} 10{sup {minus}5} r-m with 4.5 {times} 10{sup 10} particles per bunch. The 57 GeV Linac has successfully accelerated over 3 {times} 10{sup 10} particles with design invariant emittances of 3 {times} 10{sup {minus}5} r-m. Both longitudinal and transverse wakefields affect strongly the trajectory and emittance corrections used for operations. The Arc systems routinely transport decoupled and betatron matched beams. In the Final Focus, the beams are chromatically corrected and demagnified producing spot sizes of 2 to 3 {mu}m at the focal point. Spot sizes below 2 {mu}m have been made during special tests. Instrumentation and feedback systems are well advanced, providing continuous beam monitoring and pulse-by-pulse control. A luminosity of 1.6 {times} 10{sup 29} cm{sup {minus}2}sec{sup {minus}1} has been produced. Several experimental tests for a Next Linear Collider (NLC) are being planned or constructed using the SLC accelerator as a test facility. The Final Focus Test Beam will demagnify a flat 50 GeV electron beam to dimensions near 60 nm vertically and 900 nm horizontally. A potential Emittance Dynamics Test Area has the capability to test the acceleration and transport of very low emittance beams, the compression of bunch lengths to 50 {mu}m, the acceleration and control of multiple bunches, and the properties of wakefields in the very short bunch length regime.
Accelerator physics of the Stanford Linear Collider and SLC accelerator experiments towards the Next Linear Collider: The Stanford Linear Collider (SLC) was built to collide single bunches of electrons and positrons head-on at a single interaction point with single beam energies up to 55 GeV. The small beam sizes and high currents required for high luminosity operation have significantly pushed traditional beam quality limits. The Polarized Electron Source produces about 8 {times} 10{sup 10} electrons in each of two bunches with up to 28% polarization,. The Damping Rings provide coupled invariant emittances of 1.8 {times} 10{sup {minus}5} r-m with 4.5 {times} 10{sup 10} particles per bunch. The 57 GeV Linac has successfully accelerated over 3 {times} 10{sup 10} particles with design invariant emittances of 3 {times} 10{sup {minus}5} r-m. Both longitudinal and transverse wakefields affect strongly the trajectory and emittance corrections used for operations. The Arc systems routinely transport decoupled and betatron matched beams. In the Final Focus, the beams are chromatically corrected and demagnified producing spot sizes of 2 to 3 {mu}m at the focal point. Spot sizes below 2 {mu}m have been made during special tests. Instrumentation and feedback systems are well advanced, providing continuous beam monitoring and pulse-by-pulse control. A luminosity of 1.6 {times} 10{sup 29} cm{sup {minus}2}sec{sup {minus}1} has been produced. Several experimental tests for a Next Linear Collider (NLC) are being planned or constructed using the SLC accelerator as a test facility. The Final Focus Test Beam will demagnify a flat 50 GeV electron beam to dimensions near 60 nm vertically and 900 nm horizontally. A potential Emittance Dynamics Test Area has the capability to test the acceleration and transport of very low emittance beams, the compression of bunch lengths to 50 {mu}m, the acceleration and control of multiple bunches, and the properties of wakefields in the very short bunch length regime.
Accelerator prospects for photon-photon physics: This paper provides an overview of the accelerators in the world where two-photon physics could be carried out in the future. The list includes facilities where two-photon physics is already an integral part of the scientific program but also mentions some other machines where initiating new programs may be possible.
Accelerator prospects for photon-photon physics: This paper provides an overview of the accelerators in the world where two-photon physics could be carried out in the future. The list includes facilities where two-photon physics is already an integral part of the scientific program but also mentions some other machines where initiating new programs may be possible.
Accelerator research studies: The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks.
Accelerator Research Studies. Technical Progress Report, June 1, 1991--May 31, 1992: The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks.
Accelerator simulation using computers: Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a multi-track'' simulation and analysis code can be used for these applications.
Accelerator simulation using computers: Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a ``multi-track`` simulation and analysis code can be used for these applications.
Accelerator structure work for NLC: The NLC design achieves high luminosity with multiple bunches in each RF pulse. Acceleration of a train of bunches without emittance growth requires control of long range dipole wakefields. SLAC is pursuing a structure design which suppresses the effect of wakefields by varying the physical dimensions of successive cells of the disk-loaded traveling wave structure in a manner which spreads the frequencies of the higher mode while retaining the synchronism between the electrons and the accelerating mode. The wakefields of structures incorporating higher mode detuning have been measured at the Accelerator Test Facility at Argonne. Mechanical design and brazing techniques which avoid getting brazing alloy into the interior of the accelerator are being studied. A test facility for high-power testing of these structures is complete and high power testing has begun.
Accelerator structure work for NLC: The NLC design achieves high luminosity with multiple bunches in each RF pulse. Acceleration of a train of bunches without emittance growth requires control of long range dipole wakefields. SLAC is pursuing a structure design which suppresses the effect of wakefields by varying the physical dimensions of successive cells of the disk-loaded traveling wave structure in a manner which spreads the frequencies of the higher mode while retaining the synchronism between the electrons and the accelerating mode. The wakefields of structures incorporating higher mode detuning have been measured at the Accelerator Test Facility at Argonne. Mechanical design and brazing techniques which avoid getting brazing alloy into the interior of the accelerator are being studied. A test facility for high-power testing of these structures is complete and high power testing has begun.
Accelerator technology for bright radiation beam: We review the current and future accelerator technologies for generation of high brightness radiation beam.
Accelerator technology for bright radiation beam: We review the current and future accelerator technologies for generation of high brightness radiation beam.
Accelerator transmutation of {sup 129}I: Iodine-129 is one of several long-lived reactor products that is being considered for transmutation by the Los Alamos Accelerator Transmutation of Waste (ATW) program. A reasonable rate of transmutation of 1291 is possible in this system because of the anticipated high neutron flux generated from the accelerator. This report summarizes previous papers dealing with the transmutation of 1291 where reactor technologies have been employed for neutron sources. The transmutation process is considered marginal under these conditions. Presented here are additional information concerning the final products that could be formed from the transmutation process in the ATW blanket. The transmutation scheme proposes the use of solid iodine as the target material and the escape of product xenon from the containers after van Dincklange (1981). Additional developmental plans are considered.
Accelerator transmutation of sup 129 I: Iodine-129 is one of several long-lived reactor products that is being considered for transmutation by the Los Alamos Accelerator Transmutation of Waste (ATW) program. A reasonable rate of transmutation of 1291 is possible in this system because of the anticipated high neutron flux generated from the accelerator. This report summarizes previous papers dealing with the transmutation of 1291 where reactor technologies have been employed for neutron sources. The transmutation process is considered marginal under these conditions. Presented here are additional information concerning the final products that could be formed from the transmutation process in the ATW blanket. The transmutation scheme proposes the use of solid iodine as the target material and the escape of product xenon from the containers after van Dincklange (1981). Additional developmental plans are considered.
Accident information needs: A Five-step methodology has been developed to evaluate information needs for nuclear power plants under accident conditions and the availability of plant instrumentation during severe accidents. Step 1 examines the credible accidents and their relationships to plant safety functions. Step 2 determines the information personnel involved in accident management will need to understand plant behavior. Step 3 determines the capability of the instrumentation to function properly under severe accident conditions. Step 4 determines the conditions expected during the identified severe accidents. Step 5 compares the instrument capabilities and the severe accident conditions to evaluate the availability of the instrumentation to supply needed plant information.
Accident information needs: A Five-step methodology has been developed to evaluate information needs for nuclear power plants under accident conditions and the availability of plant instrumentation during severe accidents. Step 1 examines the credible accidents and their relationships to plant safety functions. Step 2 determines the information personnel involved in accident management will need to understand plant behavior. Step 3 determines the capability of the instrumentation to function properly under severe accident conditions. Step 4 determines the conditions expected during the identified severe accidents. Step 5 compares the instrument capabilities and the severe accident conditions to evaluate the availability of the instrumentation to supply needed plant information.
Accident investigation of the electrical shock incident at the PG and E PVUSA site Davis, California: This report summarizes the findings of the Accident Investigation Team (Team) assembled in response to a request from Pacific Gas and Electric Company (PG and E) to the US Department of Energy (DOE) to understand the events surrounding the electric shock of a worker at the PVUSA site in Davis, California and to provide recommendations to prevent such events from recurring. The report gives complete details on the sequence of events surrounding the accident and identifies 27 facts related to accident itself. Four technical deficiencies in the electrical systems which require further investigation were identified. The Team believes that the root cause of this accident was related to the absence of a proactive organizational entity responsible for overall health and safety on the site. Two contributing factors were identified. First, the prototype nature and associated operational difficulties of the electrical inverter resulted in large maintenance demands. Second, several of the injured employee`s co-workers noted that he occasionally failed to use appropriate personal protective equipment, but they never reported this practice to management. The direct cause of this accident was the failure of the injured employee to wear appropriate personal protective equipment (i.e., rubber gloves). Based on the review of the facts established in this investigation, five recommendations are presented to the funding agencies to reduce the possibility of future accidents at the PVUSA site.
Accounting for the effect of TDS and NCG on Salton Sea reservoir response: The Salton Sea reservoir, located in Imperial County, Ca., is unique in several ways from most liquid-dominated geothermal reservoirs that have been developed to date. One of these differences is the presence of hyper-saline brines containing up to 28% TDS (Total Dissolved Solids) and up to 0.2% NCG (Non-Condensible Gas). A simple material and energy balance model has been developed to study the effect of TDS and NCG on Salton Sea reservoir response. This study demonstrated that during the development of a two-phase system the partitioning of the NCG into the vapor phase and the consequential concentration of the TDS in the brine drastically alters the reservoir fluid properties. In modeling pressure depletion of hyper-saline reservoirs, such as the Salton Sea, these changes in reservoir fluid composition were shown to seriously affect the simulation results. As a result of these findings, a compositional fluid property package was developed using published data on H{sub 2}O-CO{sub 2}-NaCl mixtures. This fluid property package was then incorporated into the simulation program used by Unocal. Validation of the fluid property package in this simulation program was made using measured reservoir temperature, surface enthalpy, and surface flash data. The development of a compositional simulation program for geothermal applications has advanced our ability to study depletion mechanisms that are sensitive to compositional changes. This program is currently being used to study the effect of injection and steam cap development on long term operations and to develop a field model of the Salton Sea reservoir.
Accrediting industrial safety training programs: There are job-specific training requirements established by regulations that Impose stringent training requirements on a contractor, for example, the Occupational Safety Health Act (OSHA). Failure to comply with OSHA training requirements can result in severe penalties being levied against a company. Although an accredited training program is expensive, it is a possible solution for minimizing risks associated with job-specific training requirements for employees. Operating DOE contractors direct approximately 10 percent of the operating funds toward training activities. Training needs for contractors span a broad range, from requirements awareness training for managers, to general training required on a one-time basis for all employees, to highly specialized training programs for employees involved In clean-up operations at hazardous waste sites. With this kind of an investment in training, it is logical to maximize the most return on an investment of training funds and to limit exposure to liability suits whenever possible. This presentation will provide an overview of accredited industrial safety programs. The criteria for accredited industrial safety programs will be defined. The question of whether accredited training programs are necessary will be examined. Finally, advantages and disadvantages will be identified for accrediting industrial safety training programs.
Accrediting industrial safety training programs: There are job-specific training requirements established by regulations that Impose stringent training requirements on a contractor, for example, the Occupational Safety & Health Act (OSHA). Failure to comply with OSHA training requirements can result in severe penalties being levied against a company. Although an accredited training program is expensive, it is a possible solution for minimizing risks associated with job-specific training requirements for employees. Operating DOE contractors direct approximately 10 percent of the operating funds toward training activities. Training needs for contractors span a broad range, from requirements awareness training for managers, to general training required on a one-time basis for all employees, to highly specialized training programs for employees involved In clean-up operations at hazardous waste sites. With this kind of an investment in training, it is logical to maximize the most return on an investment of training funds and to limit exposure to liability suits whenever possible. This presentation will provide an overview of accredited industrial safety programs. The criteria for accredited industrial safety programs will be defined. The question of whether accredited training programs are necessary will be examined. Finally, advantages and disadvantages will be identified for accrediting industrial safety training programs.
The accuracy of beam-beam diagnostics for circular colliders: We investigate the potential of beam-beam deflection techniques for the determination of spot sizes, tilt angle, centering, and angular divergence for circular colliders. Achievable accuracies for all measured quantities are estimated.
The accuracy of beam-beam diagnostics for circular colliders: We investigate the potential of beam-beam deflection techniques for the determination of spot sizes, tilt angle, centering, and angular divergence for circular colliders. Achievable accuracies for all measured quantities are estimated.
An accurate formulation of the solubility of CO₂ in water, for geothermal applications: The solubility correlations for the H{sub 2}O-CO{sub 2} system applied so far for numerical simulation of geothermal reservoir and well flows are crude. This is due, at least partly, to the significant disagreement existing between the solubility models and results published in the specialized literature. In this work we analyze the reasons underlying this disagreement. On this basis, we propose a thermodynamically correct, and numerically accurate model for the solubility of carbon dioxide in water. Its range of validity is up to 350 C and 500 bar. Our main contributions are: (a) the adoption of an equation of state for the gas phase that realistically accounts for the non-ideal behavior of both components and that of the mixture, within the P-T range considered; and (b) to accurately include the effects of temperature and pressure on the solubility of carbon dioxide in the liquid phase. The proposed model fits the available phase equilibrium data for the H{sub 2}O-CO{sub 2} system nicely. In particular, it does not present the severe conflict between the linearity of the model and the lack of linearity of the data, evident in earlier models. The tight fit obtained with our model indicates that the complexities of H{sub 2}-CO{sub 2} phase equilibrium are well represented by it.
Accurate Measure by Weight of Liquids in Industry: This research's focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.
Accurate Measure by Weight of Liquids in Industry. Final Report: This research`s focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.
Accurate plutonium waste measurements using the {sup 252}Cf add-a- source technique for matrix corrections: We have developed a new measurement technique to improve the accuracy and sensitivity of the nondestructive assay (NDA) of plutonium scrap and waste. The 200-{ell} drum assay system uses the classical NDA method of counting passive-neutron coincidences from plutonium but has added the new features of ``add-a-source`` to improve the accuracy for matrix corrections and statistical techniques to improve the low-level detectability limits. The add-a-source technique introduces a small source of {sup 252}Cf (10{sup {minus}8} g) near the external surface of the sample drum. The drum perturbs the rate at which coincident neutrons from the {sup 252}Cf are counted. The perturbation provides the data to correct for the matrix and plutonium inside the drum. The errors introduced from matrix materials in 200-{ell} drums have been reduced by an order of magnitude using the add-a-source technique. In addition, the add-a-source method can detect unexpected neutron-shielding material inside the drum that might hide the presence of special nuclear materials. The detectability limit of the new waste-drum assay system for plutonium is better than prior systems for actual waste materials. For the in-plant installation at a mixed-oxide fabrication facility, the detectability limit is 0.73 mg of {sup 24O}Pu (or 2.3 mg of high-burnup plutonium) for a 15-min. measurement. For a drum containing 100 kg of waste, this translates to about 7 nCi/g. This excellent sensitivity was achieved using a special low-background detector design, good overhead shielding, and statistical techniques in the software to selectively reduce the cosmic-ray neutron background.
Accurate plutonium waste measurements using the sup 252 Cf add-a- source technique for matrix corrections: We have developed a new measurement technique to improve the accuracy and sensitivity of the nondestructive assay (NDA) of plutonium scrap and waste. The 200-{ell} drum assay system uses the classical NDA method of counting passive-neutron coincidences from plutonium but has added the new features of add-a-source'' to improve the accuracy for matrix corrections and statistical techniques to improve the low-level detectability limits. The add-a-source technique introduces a small source of {sup 252}Cf (10{sup {minus}8} g) near the external surface of the sample drum. The drum perturbs the rate at which coincident neutrons from the {sup 252}Cf are counted. The perturbation provides the data to correct for the matrix and plutonium inside the drum. The errors introduced from matrix materials in 200-{ell} drums have been reduced by an order of magnitude using the add-a-source technique. In addition, the add-a-source method can detect unexpected neutron-shielding material inside the drum that might hide the presence of special nuclear materials. The detectability limit of the new waste-drum assay system for plutonium is better than prior systems for actual waste materials. For the in-plant installation at a mixed-oxide fabrication facility, the detectability limit is 0.73 mg of {sup 24O}Pu (or 2.3 mg of high-burnup plutonium) for a 15-min. measurement. For a drum containing 100 kg of waste, this translates to about 7 nCi/g. This excellent sensitivity was achieved using a special low-background detector design, good overhead shielding, and statistical techniques in the software to selectively reduce the cosmic-ray neutron background.

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