Accelerating the Loop Expansion (open access)

Accelerating the Loop Expansion

This thesis introduces a new non-perturbative technique into quantum field theory. To illustrate the method, I analyze the much-studied phi/sup 4/ theory in two dimensions. As a prelude, I first show that the Hartree approximation is easy to obtain from the calculation of the one-loop effective potential by a simple modification of the propagator that does not affect the perturbative renormalization procedure. A further modification then susggests itself, which has the same nice property, and which automatically yields a convex effective potential. I then show that both of these modifications extend naturally to higher orders in the derivative expansion of the effective action and to higher orders in the loop-expansion. The net effect is to re-sum the perturbation series for the effective action as a systematic ''accelerated'' non-perturbative expansion. Each term in the accelerated expansion corresponds to an infinite number of terms in the original series. Each term can be computed explicitly, albeit numerically. Many numerical graphs of the various approximations to the first two terms in the derivative expansion are given. I discuss the reliability of the results and the problem of spontaneous symmetry-breaking, as well as some potential applications to more interesting field theories. 40 refs.
Date: July 29, 1986
Creator: Ingermanson, R.
Object Type: Report
System: The UNT Digital Library
Accelerator and final focus model for an induction Linac based HIF system study (open access)

Accelerator and final focus model for an induction Linac based HIF system study

An overview of the assumptions and models incorporated in the ongoing Induction-Linac-based, HIF System Assessment is presented. Final transport, compression and final focus pose constraints which form a critical link between the accelerator and target requirements. A recent analysis has shown that system costs may be considerably reduced by the use of multiply charges ions. The assumptions underlying this direction are described.
Date: July 1, 1986
Creator: Lee, Edward P.
Object Type: Article
System: The UNT Digital Library
ACTVE News, Volume 17, Number 4, July/August 1986 (open access)

ACTVE News, Volume 17, Number 4, July/August 1986

Newsletter issued by the Advisory Council for Technical-Vocational Education in Texas discussing news, events, and other relevant information related to technical and vocational education for adults in Texas.
Date: July 1986
Creator: Advisory Council for Technical-Vocational Education in Texas
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Advanced concepts for acceleration (open access)

Advanced concepts for acceleration

Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)
Date: July 1, 1986
Creator: Keefe, D.
Object Type: Article
System: The UNT Digital Library
Analysis of data bases for health services research on dementia (open access)

Analysis of data bases for health services research on dementia

This report offers different sources of data regarding different forms of dementia, as well as illustrations and applications in a different settings.
Date: July 1986
Creator: Liu, Korbin
Object Type: Report
System: The UNT Digital Library
Analysis, Volume 7, Number 7, July 1986 (open access)

Analysis, Volume 7, Number 7, July 1986

Periodic newsletter discussing information related to legislation, state finance, and other topics related to Texas government. This issue focuses on transportation appropriations, biennial transportation spending, financing highways, DHPT expenditures, roads and traffic, prime targets for the legislature, and more.
Date: July 1986
Creator: Texas Research League
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Anomalous dimensions of multiquark bound states (open access)

Anomalous dimensions of multiquark bound states

The evolution of six-quark color-singlet state distribution amplitudes is formulated as an application of perturbative quantum chromodynamics to nuclear wave functions. We present a general method of solving the evolution equation for multiquark bound states and predict the asymptotic Q/sup 2/ slope for the deuteron charge form factor as a result.
Date: July 1, 1986
Creator: Ji, Cheung-Ryong
Object Type: Article
System: The UNT Digital Library
Background radiation in the SLC ir from collimators and tune-up dumps in the ARCS (open access)

Background radiation in the SLC ir from collimators and tune-up dumps in the ARCS

There are various beam intercepting devices between the interaction point and the beam dumps of the SLC. Of these, the adjustable collimators, a fixed collimator, and the tune-up dumps are expected to intercept enough of the beam to warrant calculating the fluxes inside the interaction hall from them. The fluences of neutrons and photons in the interaction hall from these sources. Whether the beam has passed the interaction point or not is considered important in choosing a source term, primarily for photons. Neutron calculations are done only for giant resonance neutrons. (LEW)
Date: July 8, 1986
Creator: Jenkins, T.M.
Object Type: Report
System: The UNT Digital Library
Bench Marks for School District Budgets in Texas: 1986 (open access)

Bench Marks for School District Budgets in Texas: 1986

Annual statistical report suggesting benchmarks for school budgeting based on financial, personnel, and taxing information submitted by local school districts to state agencies.
Date: July 1986
Creator: Texas Research League
Object Type: Report
System: The Portal to Texas History
Bioaccumulation and food chain transfer of corrosion products from radioactive stainless steel (open access)

Bioaccumulation and food chain transfer of corrosion products from radioactive stainless steel

Two sets of experiments were conducted to determine if corrosion products from radioactive Type 347 stainless steel could be biologically transferred from sediment through a marine food chain, and whether corrosion products dissolved in seawater could be bioaccumulated and then eliminated. Corrosion products containing /sup 60/Co and /sup 63/Ni from the radioactive stainless steel were introduced into marine sediments. Infaunal polychaete worms exposed to these sediments bioaccumulated the radionuclides. The feeding of these worms to shrimp and fish resulted in a trophic transfer of the radioactive products across a one-step food chain. The magnitude of the transfers are described in terms of transfer factors. Dissolved corrosion products as measured by the radionuclides were also bioaccumulated by shrimp and fish concentrating more than fish. Concentration factors were calculated.
Date: July 1, 1986
Creator: Young, J. S.
Object Type: Report
System: The UNT Digital Library
Bulletin on Texas State Finance: 1986, Number 1 (open access)

Bulletin on Texas State Finance: 1986, Number 1

Periodic bulletin analyzing issues related to Texas legislation. This issue focuses on the effects of the oil market crash on the Texas state budget.
Date: July 25, 1986
Creator: Texas Research League
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Charge-exchange measurements of MHD activity during neutral beam injection in the Princeton Large Torus and the Poloidal Divertor Experiment (open access)

Charge-exchange measurements of MHD activity during neutral beam injection in the Princeton Large Torus and the Poloidal Divertor Experiment

The horizontally scanning, multiangle charge-exchange analyzers on the Princeton Large Torus (PLT) and the Poloidal Divertor Experiment (PDX) were used to study the effects of MHD activity on the background ion distribution function and on the beam ion slowing-down process during high-power neutral injection. Sawtooth oscillations were observed in the fast ion flux on PLT and PDX, and measurements with neutral beams providing local neutral density enhancement indicate that ions are transported radially when these events occur. With near-perpendicular injection in PDX, at the lower toroidal fields necessary to maximize beta, rapid, repetitive bursts of greatly enhanced charge-exchange flux were observed. These are associated with the ''fishbone'' MHD instability, and a substantial depletion of the perpendicular slowing-down spectrum below the injection energy was seen. A simple phenomenological model for this loss mechanism was developed, and its use in simulation codes has been successful in providing good agreement with the data. The behavior and characteristics of this model are well matched by the direct theoretical calculations.
Date: July 1, 1986
Creator: Goldston, R. J.; Kaita, R.; Beiersdorfer, P.; Gammel, G.; Herndon, D. L.; McCune, D. C. et al.
Object Type: Report
System: The UNT Digital Library
Compact torus accelerator: a driver for ICF. Revision 1 (open access)

Compact torus accelerator: a driver for ICF. Revision 1

We have carried out further investigations of technical issues associated with using a compact torus (CT) accelerator as a driver for inertial confinement fusion (ICF). In a CT accelerator, a magnetically-confined torus-shaped plasma is compressed, accelerated and focused by two concentric electrodes. Here, we evaluate an accelerator point design with a capacitor bank energy of 9.2 MJ. Modeled by a O-D code, the system produces a xenon plasma ring with a radius of 0.73 cm, a velocity of 4 x 10/sup 7/ m/s, and a mass of 4.4 ..mu..g. The plasma ring energy available for fusion is 3.8 MJ, a 40% driver efficiency. Ablation and magnetic pressures of the point design, a due to CT acceleration, are analyzed. Pulsed-power switching limitations and driver cost analysis are also presented. Our studies confirm the feasibility of producing a ring to induce fusion with acceptable gain. However, some uncertainties must be resolved to establish viability.
Date: July 31, 1986
Creator: Tobin, M. T. & Morse, E. C.
Object Type: Article
System: The UNT Digital Library
Comparison of q anti qg and q anti q. gamma. events in e/sup +/e/sup -/ annihilation at PEP (open access)

Comparison of q anti qg and q anti q. gamma. events in e/sup +/e/sup -/ annihilation at PEP

In comparing the particle flow in the event plane of three-jet (q anti qg) events and of radiative annihilation events (q anti q..gamma..) for similar kinematic configurations, two PEP experiments find a significant decrease in particle density in the angular region opposite to the gluon jet in q anti qg events, relative to the particle density in the region opposite to the photon in q anti q..gamma.. events. The effect is predicted both by QCD and by phenomenological string models. 5 refs., 5 figs.
Date: July 1, 1986
Creator: Hofmann, W.
Object Type: Article
System: The UNT Digital Library
Composition of high fission product wastes resulting from future reprocessing of commercial nuclear fuels (open access)

Composition of high fission product wastes resulting from future reprocessing of commercial nuclear fuels

Pacific Northwest Laboratory studies, aimed at defining appropriate glass compositions for future disposal of high-level wastes, have developed composition ranges for the waste that will likely result during reprocessing of Light Water Reactor (LWR) and Liquid Metal Reactor (LMR) fuels. The purpose of these studies was to provide baseline waste characterizations for possible future commercial high-level waste so that waste immobilization technologies (e.g., vitrification) can be studied. Ranges in waste composition are emphasized because the waste will vary with time as different fuels are reprocesses, because choice of process chemicals is nuclear, and because fuel burnups will vary. Consequently, composition ranges are based on trends in fuel reprocessing procedures and on achievable burnups in operating reactors. In addition to the fission product and actinide elements, which are the primary hazardous materials in the waste, likely composition ranges are given for inert elements that may be present in the waste. These other elements may be present because of being present in the fuel, because of being added as process chemical during reprocessing, because of being added during equipment decontamination, or because of corrosion of plant equipment and/or fuel element cladding. This report includes a discussion of the chemicals added in variation …
Date: July 1, 1986
Creator: Swanson, J.L
Object Type: Report
System: The UNT Digital Library
Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984 (open access)

Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, /sup 137/Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of /sup 137/Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. /sup 90/Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of /sup 60/Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of /sup 60/Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of /sup 207/Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of /sup 207/Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, …
Date: July 1, 1986
Creator: Noshkin, V. E.; Wong, K. M.; Eagle, R. J.; Jokela, T. A. & Brunk, J. A.
Object Type: Report
System: The UNT Digital Library
Conformal invariance on Calabi-Yau spaces (open access)

Conformal invariance on Calabi-Yau spaces

The possibility of superstring compactification on Calabi-Yau manifolds is analyzed. Despite the apparent non-zero ..beta.. function at four loop order, it is possible to construct a conformally invariant sigma model on a Calabi-Yau manifold. The background metric is not Ricci flat, but is related to the Ricci flat metric through a (non-local) field redefinition. 9 refs.
Date: July 1, 1986
Creator: Nemeschansky, D.
Object Type: Article
System: The UNT Digital Library
Control of beam dynamics in high energy induction linacs (open access)

Control of beam dynamics in high energy induction linacs

The Advent of laser-ion-guiding in the Advanced test Accelerator along with the development of accelerator cavities optimized with respect to beam breakup coupling impedence now make it possible to consider a new class of high current, high emergy linear induction accelerators. The control of the beam breakup and other instabilities by laser guiding and by various magnetic focusing schemes will be discussed along with the scaling laws for the design of such machines to minimize the growth of the beam breakup instability. Many linacs, particularly induction linacs are limited in performance by the beam breakup (BBU) instability. The instability is found in two forms. In the first form the accelerating cavities communicate with one another through interaction with the beam and through propagation of cavity fields through the accelerator structure. In the second form which is the more virulent of the two, the cavities couple to each other only through their interactions with the beam. It is this second form of PPU that will be discussed in this paper.
Date: July 29, 1986
Creator: Caporaso, G.J.
Object Type: Article
System: The UNT Digital Library
Converging xenon shock waves driven by megagauss magnetic fields (open access)

Converging xenon shock waves driven by megagauss magnetic fields

We attempted to implode a conducting metal linear at high velocity, and our failure to do so led to switching, or rapidly transferring the field from pushing an aluminum conductor to snow-plowing a half-atmosphere of xenon gas. We successfully initiated convergent xenon gas shocks with the use of a magnetohydrodynamic switch and coaxial high-explosive, flux-compression generators. Principal diagnostics used to study the imploding xenon gas were /sup 133/Xe radioactive tracers, continuous x-ray absorption, and neutron output. We compressed the xenon gas about five to sixfold at a velocity of 10 cm/..mu..s at a radius of 4 cm. The snowplow efficiency was good; going from 13- to 4-cm radius, we lost only about 20% of the mass. The temperature of the imploded sheath was determined by mixing deuterium with the xenon and measuring the neutron output. Using reasonable assumptions about the amount, density, and uniformity of the compressed gas, we estimate that we reached temperatures as high as 155 eV. Energy-loss mechanisms that we encountered included wall ablation and Taylor instabilities of the back surface.
Date: July 1, 1986
Creator: Shearer, J. W. & Steinberg, D. J.
Object Type: Article
System: The UNT Digital Library
Coupled-channel analysis of neutron scattering from /sup 12/C between 9 and 15 MeV (open access)

Coupled-channel analysis of neutron scattering from /sup 12/C between 9 and 15 MeV

A deformed and energy dependent phenomenological optical model potential and coupled-channel formalism for deformed nuclei have been used in the analysis of elastic and inelastic (Q = 4.439 MeV) scattering, and analyzing power for neutrons scattered from /sup 12/C in the energy range of 9 to 15 MeV. 6 refs., 1 fig., 1 tab.
Date: July 1, 1986
Creator: Hansen, L. F. & Meigooni, A. S.
Object Type: Article
System: The UNT Digital Library
Coupling impedance of laminated magnets in the booster (open access)

Coupling impedance of laminated magnets in the booster

The magnets in the Fermilab Booster Synchrotron are laminated in order to minimize the eddy current losses and associated field distortions expected at a 15 Hz operating frequency. To further reduce the eddy current losses, the vacuum chamber is outside the magnet, hence allowing the beam induced wall currents to see the laminations directly. This note estimates the coupling impedances and beam energy loss per turn caused by the exposed laminations.
Date: July 11, 1986
Creator: Shafer, R. E.
Object Type: Report
System: The UNT Digital Library
The Cross Section, Volume 32, Number 7, July 1986 (open access)

The Cross Section, Volume 32, Number 7, July 1986

Monthly newsletter of the High Plains Underground Water Conservation District No. 1, discussing the field of underground water. Topics include profiles of water conservation research, annual pre-plant soil moisture survey data, annual Winter Water Level measurement data, and information about the latest water conservation tips.
Date: July 1986
Creator: High Plains Underground Water Conservation District No. 1 (Tex.)
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Cumulative releases of radionuclides from uncontained waste packages (open access)

Cumulative releases of radionuclides from uncontained waste packages

This report describes mathematical predictions for the migration of radionuclides from an emplaced radioactive waste container. The model assumes a spherical-equivalent waste solid surrounded by backfill but neglects the effect of decay heat. 7 refs., 2 tabs. (TEM)
Date: July 1, 1986
Creator: Lee, W. W. L.; Kim, C. L.; Chambre, P. L. & Pigford, T. H.
Object Type: Article
System: The UNT Digital Library
DC septum magnets for the damping rings of the SLC SLAC Linear Collider (open access)

DC septum magnets for the damping rings of the SLC SLAC Linear Collider

The injection/extraction systems of the 1.21 GeV Stanford Linear Collider (SLC) damping rings uses four pairs of water cooled septum magnets. Each pair consists of a thin-septum, low-field (3 mm, 3 kilogauss) magnet plus a thick-septum, high-field (12 mm, 8 kilogauss) model. In the latest design cooling reliability was improved by using stainless-steel tubing imbedded in the copper. The operating current in each is 2600 amperes, at a density of up to 120 amperes per mmS. Plasma-sprayed alumina is used to provide electrical insulation. The magnet system is compatible with 10 Z torr ultra-high vacuum. The magnet design, fabrication, and measurements are described.
Date: July 1, 1986
Creator: Bijleveld, J.; Peterson, J. M. & Jensen, D.
Object Type: Article
System: The UNT Digital Library