This paper discusses the following on quantum gravity: 2 + 1 gravity as a Chern-Simons theory; quantization; dynamics; the Braid group; and the emergence of space and time. 16 refs., 3 figs. (LSP)

A high-gradient, S-band microwave gun with a thermionic cathode is being developed in a collaborative effort by AET, Varian, and SSRL. A prototype design using an upgraded Varian dispenser cathode mounted with thermal isolation directly in the first half-cell of a 1-1/2 cell, side-coupled, standing-wave cavity has been fabricated and is being tested. Optimization of the cavity shape and beam formation was done using SUPERFISH, MASK, and PARMELA. An overview of design details, as well as the status of in-progress beam tests, will be presented. 9 refs., 6 figs.

In spite of the significantly increased attention atmospheric ozone has received over the last two decades or so, a fully quantitative understanding of the three-dimensional ozone structure remains unavailable. In the past, one-dimensional (vertical column) models have provided most of the quantitative simulations of atmospheric chemical systems, because these models can treat large ensembles of chemical process economically. More recently, two-dimensional (meridional cross section) models have become popular, in part because of increasing computer capabilities. There has been little work using a sophisticated 3-D GCM coupled with a comprehensive photochemical model to study the chemical-dynamical interactions involving the ozone abundance. Namely, either the dynamics or the chemistry is too simplified in most of the existing models. Relatively more advanced photochemistry has been included in the stratospheric models (dealing the vertical domain from 20 to 70 km above the surface) at the expense of tropospheric details. An important motivation for this research has been the desire to estimate the magnitude of changes in the ozone layer induced by anthropogenic perturbations such as the injection of oxides of nitrogen and chlorine compounds. Accordingly, the attempt has been to develop a complete but feasible photochemical scheme and to combine it with the Los …

A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predictions will be validated against test data using the ANL bulk calorimeter. 11 refs., 6 figs.

Discussed is a system for storing 3-D measurements of points that relates the coordinate system of the measurement device to the global coordinate system. The program described here used object-oriented FORTH to store the measured points as sons of the measuring device location. Conversion of local coordinates to absolute coordinates is performed by passing messages to the point objects. Modifications to the object-oriented FORTH system are also described. 1 ref.

We report first-principles local-density functional pseudopotential calculations of static and dynamic electronic structure properties of crystalline 3-D trans--(CH)/sub x/. We find a broken symmetry ground state of P2/sub 1//a symmetry with in-phase dimerizations. Using a Green's function technique, we show that the 3-D character of the electronic band edge states strongly suppresses self-trapping, destabilizing polarons and possibly bipolarons as well in perfectly ordered 3-D trans--(CH)/sub x/. 26 refs.

The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m{sup 2} at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-{beta} plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen …

In this paper, the final preparations for bringing the University of Maryland's 10 GHz, 30 MW gyroklystron experiment on-line are discussed. We describe the initial operation of the modulator and the acceptance tests performed on the electron gun. We explain the enhanced circuit modelling and present a two-cavity design which predicts an efficiency of 33% and a gain of 27 dB. The realization of the design is also discussed. In addition, we briefly discuss the output waveguide and the diagnostics for beam and rf characterization. Finally, a four-cavity circuit design is presented with its predicted operating parameters that can achieve the necessary gain and efficiency required for accelerator application. 14 refs., 11 figs., 5 tabs.

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Fermilab has plans for a comprehensive accelerator upgrade to open new possibilities for both the fixed target and collider experimental programs. An early step in this program is to increase the energy of the linac from 200 to 400 MeV by replacing the last four of its nine 201 MHz Alvarez tanks with twenty-eight 805 MHz side-coupled cavity chains operating at about 8 MV/m average axial field. The principal purpose is to reduce the incoherent spacecharge tuneshift at injection into the Booster which currently limits both the brightness of the beam, an important determinant of collider luminosity, and total intensity to produce both the antiprotons for the collider and the beams to fixed target experimental areas. Other consequences of higher Booster injection energy expected to contribute to some degree of higher intensity limits and improved operational characteristics include improved quality of the guide field at injection, reduced frequency swing for the rf systems, and smaller emittance for the injected beam. The linac upgrade project has moved from a 1986 study through a development project including structure models and numerical studies to a full-feature module prototyping starting this year.

Fermilab plans to upgrade the Tevatron to expand the physics research program in both the fixed target and the collider operating modes. The first phase of this program is to increase the energy of the H{sup -} linac from 200 to 400 MeV in order to reduce the incoherent space change tuneshift at injection into the Booster which can limit either the brightness or the total intensity of the beam. The linac upgrade will be achieved by replacing the last four 201 MeV, with seven 805 MHz side-coupled cavity modules operating at an average axial field of about 8 MV/m. This will allow acceleration to 400 MeV in the existing Linac enclosure. 4 refs., 3 figs., 1 tab.

The Disk and Washer (DAW) structure with four bi-periodic tees to support the washers has been studied at Fermilab for the Linac Upgrade by constructing two, 805 MHz, one-meter sections joined by a coaxial coupler. The coupler provides an rf drive port, an adjustable tuner, a vacuum port, and an enclosure for the installation of beam focussing and monitoring devices. This configuration is suitable for a high beta proton linear accelerator. The bi-periodic tee supports in the DAW structure suppress the TM{sub 11} mode at the operating frequency which has been a problem with previous designs. Frequency-mode spectra have been calculated and measured as well as the quantities Q, R/Q, and ZT{sup 2}. The structure has been evacuated and operated at high power levels and high accelerating fields. 5 refs., 4 figs., 2 tabs.

On May 22, 1989, the Japanese Ginga Team discovered a new x-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni. Its last recorded outburst was in 1938 when it rose to about 12th mag. Spectroscopic data were obtained and confirmed the nature of the outburst. Additional ground based data were obtained by us at CTIO and the VLA. The x-ray behavior of this object has been reported to be very unusual and it reached a peak of about 17 crab about one week after discovery. Since then it has varied widely in magnitude at all wavelengths at which it has been studied. We present a brief summary of the observations that have been obtained up to the time of the meeting and shortly thereafter. 5 refs., 3 figs.

My contribution to this CRP is the provision of double-differential neutron-scattering cross section data on the mono-isotopic elements Nb, Rh, In, Ho, Ta, Au, and Bi. These data cover the ranges incident neutron energies, E{sub in} = 5--8 Mev, angular range, 30--158 {degrees}, excitation energies, {approx} 2 to E{sub in}--1 MeV. In this report I will briefly review the original purpose of these measurements, indicate the assumptions and procedures required to obtain the requested cross sections, present the results of this effort, give a few examples of how these results compare to calculations made with relevant nuclear model codes, describe the data files that I have prepared for the participants of this CRP, briefly describe sources of error. An appendix contains a short discussion of some experimental concerns. 8 refs., 9 figs.

The ZTH Reversed Field Pinch (RFP) plasma confinement experiment being built at the Los Alamos National Laboratory will use magnet coils to provide ohmic heating currents in the plasma. The ohmic heating coils are supported by a structure that will allow them limited movement with respect to surrounding hardware and the connecting electrical bus work. To minimize displacement-induced stresses in the coils, flexible'' power conducting links are necessary to accommodate the relative motion between the bus work and the coils. A semi-flexible 2000 MCM jumper cable has been designed with enough flexibility to allow free movement of the coils, yet it is stiff enough to withstand large magnetically-induced lateral loads and minimize the effect of the lateral loads on the magnet coil leads. A full-power life cycle test of the jumper was performed under magnetic, thermal and dynamic loads that closely simulate the expected operating conditions. This test evaluated the structural and electrical integrity of the jumper as well as the quality and reliability of the bolted electrical connections at the jumper ends in a high-stress, cyclic-loading environment. The jumper cable design is presented with an explanation of the requirements for a semi-flexible link. A description of the life cycle …

A three-dimensional finite element thermal stress analysis of the RH TRU experiments in WIPP Room T has been performed. This analysis aids in the interpretation of the borehole closure results being obtained from the Room T experiments and helps in assessing potential performance impacts in a typical storage room, during the waste retrieval period. Computed results are presented and compared to available in situ data, and a qualitative agreement between measured and computed closures is seen. 9 refs., 10 figs.

Absorption experiments have been performed on electron-beam pumped rare gases (argon and krypton) as a function of pump power using the frequency-doubled output of a tunable dye laser at 248.4 nm and 257.3 nm. Energy deposition into the gas was varied by attenuating the electron beam with one or two stainless steel screens and by filling the gas chamber with different rare gas densities. The results from two energy deposition diagnostics were compared, and found to agree within 20%. Kinetics code calculations agreed with experimental results when absorption cross sections in the code were lowered. 9 refs., 12 figs., 2 tabs.

This report contains abstracts of papers that are submitted for the 31st annual meeting of the Division of Plasma Physics, November 13--17, 1989. (LSP)

10 Hz sine wave and 2 Hz sawtooth AC magnetic measurements of he curved ALS Booster Dipole Engineering Model Magnet have been accomplished. Long curved coils were utilized to measure the integral transfer function and uniformity. Point coils and a Hall Probe were used to measure magnetic induction and its uniformity. The data were logged and processed by a Tektronix 11401 digital oscilloscope. The dependence of the effective length on the field was determined from the ratio of the integral coil signals to the point coil signals. Quadrupole and sextupole harmonics were derived from the point and integral uniformity measurements. 5 refs., 4 figs., 2 tabs.

High-explosive charges have been used to accelerate stainless steel plates to velocities of 6-7 km/s. A two-stage system has been used in which the first stage is a plane-wave detonating system that accelerates the plate down a short barrel. The second stage consists of a hollow cylindrical charge through which the moving plate passes. After an adjustable delay this charge is detonated on the outer circumference of the entry side of the charge. Flash radiographs and witness plates show no breakup in the first stage but bowing and frequent breakup in the second stage. 6 figs.

Small, light projectiles have been accelerated to high speeds using a two-stage light gas gun at Oak Ridge National Laboratory. With 35-mg plastic projectiles (4 mm in diameter), speeds of up to 4.5 km/s have been recorded. The pipe gun'' technique for freezing hydrogen isotopes in situ in the gun barrel has been used to accelerate deuterium pellets (nominal diameter of 4 mm) to velocities of up to 2.85 km/s. The primary application of this technology is for plasma fueling of fusion devices via pellet injection of hydrogen isotopes. Conventional pellet injectors are limited to pellet speeds in the range 1-2 km/s. Higher velocities are desirable for plasma fueling applications, and the two-stage pneumatic technique offers performance in a higher velocity regime. However, experimental results indicate that the use of sabots to encase the cryogenic pellets and protect them for the high peak pressures will be required to reliably attain intact pellets at speeds of {approx}3 km/s or greater. In some limited tests, lithium hydride pellets were accelerated to speeds of up to 4.2 km/s. Also, repetitive operation of the two-stage gun (four plastic pellets fired at {approx}0.5 Hz) was demonstrated for the first time in preliminary tests. The equipment …

The design of a high current heavy ion induction linac driver for inertial confinement fusion is optimized by adjusting the acceleration units along the length of the accelerator to match the beam current, energy, and pulse duration at any location. At the low energy end of the machine the optimum is a large number of electrostatically focused parallel beamlets, whereas at higher energies the optimum is a smaller number of magnetically focused beams. ILSE parallels this strategy by using 16 electrostatically focused beamlets at the low end followed by 4 magnetically focused beams after beam combining. 3 refs., 2 figs.

Neural Nets (NN) have been described as a solution looking for a problem. In the last conference, Artificial Intelligence (AI) was considered in the accelerator context. While good for local surveillance and control, its use for large complex systems (LCS) was much more restricted. By contrast, NN provide a good metaphor for LCS. It can be argued that they are logically equivalent to multi-loop feedback/forward control of faulty systems, and therefore provide an ideal adaptive control system. Thus, where AI may be good for maintaining a 'golden orbit,' NN should be good for obtaining it via a quantitative approach to 'look and adjust' methods like operator tweaking which use pattern recognition to deal with hardware and software limitations, inaccuracies or errors as well as imprecise knowledge or understanding of effects like annealing and hysteresis. Further, insights from NN allow one to define feasibility conditions for LCS in terms of design constraints and tolerances. Hardware and software implications are discussed and several LCS of current interest are compared and contrasted. 15 refs., 5 figs.

A collaborative study by Los Alamos and Brookhaven National Laboratories, supported by the Westinghouse Hanford Company, investigating a facility to produce tritium for the nation's defense needs indicates that a 1.6-GeV, 250-mA proton accelerator is required. A reference design of this accelerator starts with two parallel 125-keV injectors feeding 350-MHz radio-frequency quadrupoles (RFQ) that funnel at 2.5 MeV into a 700-MHz drift-tube linac (DTL). The DTL injects at 100 MeV into a 1400-MHz side-coupled linac (SCL). The accelerator will cost about $1.2 B and require 746 MW of electricity. 3 refs., 3 tabs.