Measurements of two- and three-particle correlations between like-sign pions produced in e/sup +/e/sup minus/ annihilation at 29 GeV center-of-mass energy are presented. The analysis is based on data taken during the period 1982--1986 using the TPC/2..gamma.. detector at PEP. Two-particle correlations are studied as a function of Q, the momentum difference as measured in the rest frame of the pion pair, and as a function of q/sub 0/, the energy difference as measured in the lab frame. The Bose-Einstein enhancement is observed when Q is small even when the energy difference, q/sub 0/, is substantial. This observation provides evidence that the Bose-Einstein correlations are best described by a model that correctly accounts for the relativistic motion of the particle sources. Three-pion correlations are measured both by using a standard three-pion correlation function, and also by using a correlation function for which the correlations between the pairs of pions within the triplet have been subtracted. The observation of three-pion correlations after pair correlations have been subtracted supports the interpretation that the observed correlations are due to Bose-Einstein interference. 56 refs.
A new position-sensitive time-of-flight neutron detection and histograming system has been developed for use at the Intense Pulsed Neutron Source. Spatial resolution of roughly 1 cm {times} 1 cm and time-of-flight resolution of {approximately}1 {mu}sec are combined in a detection system which can ultimately be expanded to cover several square meters of active detector area. This system is based on the use of arrays of cylindrical one-dimensional position-sensitive proportional counters, and is capable of collecting the x-y-t data and sorting them into histograms at time-averaged data rates up to {approximately}300,000 events/sec over the full detector area and with instantaneous data rates up to more than fifty times that. Numerous hardware features have been incorporated to facilitate initial tuning of the position encoding, absolute calibration of the encoded positions, and automatic testing for drifts. 7 refs., 11 figs., 1 tabs.
Synchrotron radiation measurements of near-threshold and broad-range (400--1500 eV) absolute photoabsorption cross sections were made for five transition metals with {plus minus}10% overall uncertainties. Fine structure details of 2p-3d autoionizing resonances are shown with better than 1.0 eV resolution for solid metals: Ti, V, Cr, Fe, Ni, and Cu. Fine structure similar to what we measured can be produced using a multi-configuration Dirac Fock (MCDF) model if a statistical distribution is assumed for the initial atomic states. Calculations were performed in intermediate coupling with configuration interactions by Mau H. Chen. The results are compared with other experimental work and theoretical methodologies. 18 refs., 7 figs.
This report starts out by discussing in details the Tax Reform Act of 1986 and its impact on local construction, it provides statistical analysis of the effects of the Tax reform Act, it discusses innovative infrastructure financing techniques, finally federal infrastructure policy options.
We discuss some current problems associated with the applications of QCD to event rates in high energy collisions. Emphasis is given to the current ambiguities and uncertainties that exist in estimates of signals and backgrounds. The production of jets and isolated photons at hadron colliders is discussed in some detail. The problems of jet definition are addressed. Some features of the events underlying the hard scattering process are discussed. 72 refs., 32 figs., 3 tabs.
The ohmic heating system for the Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) provides both the voltage for the initial breakdown phase and the energy to drive the plasma current to a value of 400 kA or greater. Providing this voltage and flux swing requires a one-turn loop voltage of about 25 volts (11 kV across the coil) and a magnetic flux swing of 2 volt- seconds. This voltage and flux swing are accomplished by charging the ohmic heating coils to 20 kA, at which point the current is commutated off into a resistor generating the 11 kV across the coil. When the current passes through zero, another power supply drives the current in the opposite polarity to 20 kA, thus completing the full 2 volt-second flux swing. This paper describes the design features and performance of the ohmic heating circuit, with emphasis on the commutation circuit. In addition, the paper describes the use of the ohmic heating system for discharge cleaning and the changeover procedure. 3 refs., 4 figs., 1 tab.
Inertial Confinement Fusion is an approach to fusion which relies on the inertia of the fuel mass to provide confinement. To achieve conditions under which this confinement is sufficient for efficient thermonuclear burn, high gain ICF targets designed to be imploded directly by laser light. These capsules are generally a spherical shell which is filled with low density DT gas. The shell is composed of an outer region which forms the ablator and an inner region of frozen or liquid DT which forms the main fuel. Energy from the driver is delivered to the ablator which heats up and expands. As the ablator expands and blows outward, the rest of the shell is forced inward to conserve momentum. In this implosion process, several features are important. We define the in-flight-aspect-ratio (IFAR) as the ratio of the shell radius R as it implodes to its thickness {Delta}R. Hydrodynamic instabilities during the implosion impose limits on this ratio which results in a minimum pressure requirement of about 100 Mbar. The convergence ratio is defined as the ratio of the initial outer radius of the ablator to the final compressed radius of the hot spot. This hot spot is the central region of the compressed fuel which is required to ignite the main fuel in high gain designs. Typical convergence ratios are 30--40. To maintain a nearly spherical shape during the implosion, when convergence ratios are this large, the flux delivered to the capsule must be uniform to a few percent. The remainder of this paper discusses the conditions necessary to achieve thermonuclear ignition in these ICF capsules.
The implosion of an ICF capsule must accomplish both compression of the main fuel to several hundred grams per cubic centimeter and heating and compression of the central region of the fuel to ignition. This report discusses the physics of these conditions.
A number of proposed irradiation processes requires bulk rather than surface exposure with intense applications of ionizing radiation. Typical examples are irradiation of food packaged into pallet size containers, processing of sewer sludge for recycling as landfill and fertilizer, sterilization of prepackaged medical disposals, treatment of municipal water supplies for pathogen reduction, etc. Volumetric processing of dense, bulky products with ionizing radiation requires high energy photon sources because electrons are not penetrating enough to provide uniform bulk dose deposition in thick, dense samples. Induction Linear Accelerator (ILA) technology developed at the Lawrence Livermore National Laboratory promises to play a key role in providing solutions to this problem. This is discussed in this paper.
The beam-beam disruption phenomena in linear colliders are increasingly seen as a source of serious problems for these machines. A plasma compensation scheme, in which the motion of the plasma electrons in the presence of the colliding beams provides neutralizing charge and current densities, has been proposed and studied. But natural alternative to this scheme is to consider the overlapping of nearly identical high energy e/sup +/ and e/sup /minus// bunches, and the collision of two such pairs - in other words, collision of two opposing relativistic positronium plasmas. It should be noticed that while the luminosity for all collisions is increased by a factor of four in this scheme, the event rate for e/sup +/e/sup /minus// collisions is only increased by a factor of two. The other factor of two corresponds to the addition of e/sup +/e/sup +/ and e/sup /minus//e/sup /minus// collisions to the interaction point. This beam compensation scheme, which has been examined through computer simulation by Balakin and Solyak in the Soviet Union, promises full neutralization of beam charges and currents. These numerical investigations have shown that plasma instabilities exist in this nominally neutral system. Although the implementation of this idea seems technically daunting, the potential benefits (beamstrahlung and disruption suppression, relaxation of final focus system constraints) are such that we should consider the physics of these collisions further. In the remainder of this paper, we theoretically analyze the issues of stability and bunch parameter tolerances in this scheme. 11 refs.
Design of the ITER vacuum vessel (VV) is driven strongly by disruption-induced forces. We use the Tokamak Simulation Code (TSC) to model disruptions for the ITER physics phase (I{sub p} = 22 MA) and predict the time evolution of currents and forces on the VV. For a plasma vertically displaced to Z{sub axis} = {minus}1.0m before disruption and decaying at a rate of < dI{sub p}/dt > {approx equal} {minus}1.0MA/ms, the induced VV current peaks at 18 MA. The maximum radial VV force F{sub R} is 56 MN/rad; the maximum vertical force F{sub Z} is 5.4 MN/rad; and the maximum VV disruption pressure is 1.0 MPa. Variations in VV resistance (20 - 160 {mu}{Omega}) and < dI{sub p}/dt > (1 - 2.5 MA/ms) do not change F{sub R} significantly. The dependence of the forces on the initial plasma displacement and < dI{sub p}/dt > behavior, and the responses of other conducting structures are discussed. 2 refs., 6 figs.
This paper discusses some concepts of future accelerators such as free electron lasers, two beam accelerator; and plasma-based adiabatic compressor. 12 refs., 10 figs., 5 tabs. (LSP)
A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles are located inside the tokamak about 1 cm outside of the limiter radius at machine potential. The success of this measurement depends on our ability to float the data acquisition system near machine potential and isolate it from the rest of the vault ground system. Our data acquisition system has 48 channels of thermistor signal conditioning, a multiplexer and digitizer section, a serial data formatter, and a fiber-optic transmitter to send the data out. Additionally, we bring timing signals to the interface through optical fibers to tell it when to begin measurement, while maintaining isolation. The receiver is an HP 200 Series computer with a serial data interface; the computer provides storage and local display for the shot temperature profile. Additionally, the computer provides temporary storage of the data until it can be passed to a shared resource management system for archiving. 2 refs., 6 figs.
A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles are located inside the tokamak about 1 cm outside of the limiter radius at machine potential. The success of this measurement depends on our ability to float the data acquisition system near machine potential and isolate it from the rest of the vault ground system. Our data acquisition system has 48 channels of thermistor signal conditioning, a multiplexer and digitizer section, a serial data formatter, and a fiber-optic transmitter to send the data out. Additionally, we bring timing signals to the interface through optical fibers to tell it when to begin measurement, while maintaining isolation. The receiver is an HP 200 series computer with a serial data interface; the computer provides storage and local display for the shot temperature profile. Additionally, the computer provides temporary storage of the data until it can be passed to a shared resource management system for archiving. 2 refs., 6 figs.
This report provides (1) a description of the coverage, benefits, financing and administration of the Japanese health insurance plans; (2) a discussion of the way in which reimbursement levels for health care providers are determined; and (3) an analysis of the way in which the provision of health care system is organized in Japan.
Design and performance of a 4.2 radiation length lead-sandwich, gas tube hodoscope are discussed. The device, measuring 1 /times/ 2 m/sup 2/ in area and 12 cm in depth, was employed in Fermi National Accelerator Laboratory experiment 705. Multiple samplings of anode wires situated within three-walled aluminum tubes were used to generate an X coordinate; similarly, capacitively coupled copper-clad strips were ganged together to yield a Y coordinate. The results reviewed are based on an analysis of electron calibration data taken during a recent six-month running period. In particular, position resolution (in millimeters) is seen to be 0.8 + 3.3/..sqrt..E + 31/E for the 9.92 mm spaced wires and 0.6 + 3.2/..sqrt..E + 32/E for the 12.5 mm strips, where E represents the electron beam energy in GeV. 5 refs., 6 figs.
This interoffice memorandum describes an incineration system to be used for incinerating wood. The system is comprised of a shredder and an incinerator. The entire process is described in detail. A brief study of particulates, carbon monoxide, carbon dioxide, and nitrogen oxides emission is presented.
The injection and penetration of bacteria into a reservoir is the most problematic and crucial of the steps in microbial enhanced recovery (MEOR). In the last phase of our work valuable information on bacterial transport in porous media was obtained. A great deal of progress was made to determine chemical bonding characteristics between adsorbed bacteria and the rock surfaces. In order to further enhance our knowledge of the effects of surface tensions on bacteria transport through porous media, a new approach was taken to illustrate the effect of liquid surface tension on bacterial transport through a sandpack column. Work in surface charge characterization of reservoir rock as a composite oxide system was also accomplished. In the last section of this report a mathematical model to simulate the simultaneous diffusion and growth of bacteria cells in a nutrient-enriched porous media is proposed.
The purpose of this paper is to provide comments on the Environmental Protection Agency (EPA) Notice in the Federal Register entitled, ``Oil and Gas Extraction Point Source Category, Offshore Subcategory; Effluent Limitations Guidelines and New Source Performance Standards; New Information and Request or Comments`` (53 FR 41356; October 21, 1988). This Notice announces the availability of new technical, economic and environmental assessment information relating to the development of Best Available Technology economically achievable (BAT and New Source Performance Standards (NSPS) regulations under the Clean Water Act governing the discharge of drilling fluids (muds) and drill cuttings from offshore oil and gas facilities. The Notice is part of a rulemaking process which formally began with the initial release of rules in August 1985 and which incorporates numerous comments and additional data received subsequent to the release of the 1985 rules. The comments in this paper will concentrate on the following five issues: Estimated project impacts are misrepresented by assuming weighted-average incremental costs of regulation. Economic impacts are inaccurate, since annual compliance costs will likely affect the number of wells drilled, by the effect of compliance costs on project economics and the reduction in industry cash flows on capital available for drilling. Initial well productivity assumptions for various scenarios do not vary with field size. The assumed lease costs, which are based on historical data, do not accurately reflect the future value of leases. The experimental decline rates assumed for the Pacific are too high.
This paper presents the results of an assessment of the potential economic impact of proposed regulations. on the discharge of drilling fluids (muds) and cuttings on US offshore undiscovered crude oil resources. These regulations include proposed Best Available Technology economically achievable (BAT) and New Source Performance Standards (NSPS) effluent limitations under the Clean Water Act governing the discharge of drilling fluids and drill cuttings from offshore oil and gas drilling operations. The impact of the proposed RAT/NSPS regulations for the drilling fluids and drill cuttings disposal on the cost of funding, developing, and producing Lower-48 offshore undiscovered crude oil resources will depend significantly on operators perceptions on the chances of failing toxicity or static sheen tests. If operators, in economically justifying their projects, assume that the fluids fail one of these tests, thereby prohibiting them from being discharged, up to 11% of the economically recoverable offshore resource would be considered uneconomic to produce. This would amount to 845 million barrels of oil at an oil price around $25 per barrel. On the other hand, if operators are willing co take their chances and see if their fluids fail one of these tests, then, based on EPA`s assumptions concerning forecast fluid use and static sheen and toxicity test failure rates, up to 4% of the offshore undiscovered resource would be impacted, amounting to lost reserves of up to 270 million barrels.
It is the purpose of the NRAD to provide an analysis of the range of potential consequences of accidents which have been identified that are associated with the launching and deployment of the Galileo mission spacecraft. The specific consequences analyzed are those associated with the possible release of radioactive material (fuel) of the Radioisotope Thermoelectric Generators (RTGs). They are in terms of radiation doses to people and areas of deposition of radioactive material. These consequence analyses can be used in several ways. One way is to identify the potential range of consequences which might have to be dealt with if there were to be an accident with a release of fuel, so as to assure that, given such an accident, the health and safety of the public will be reasonably protected. Another use of the information, in conjunction with accident and release probabilities, is to estimate the risks associated with the mission. That is, most space launches occur without incident. Given an accident, the most probable result relative to the RTGs is complete containment of the radioactive material. Only a small fraction of accidents might result in a release of fuel and subsequent radiological consequences. The combination of probability with consequence is risk, which can be compared to other human and societal risks to assure that no undue risks are implied by undertaking the mission. 4 refs., 11 figs., 31 tabs.
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