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A report is given of the activities of the 1977 ISABELLE Summer Workshop, held from July 18 to 29, 1977 at the Brookhaven National Laboratory. An abstract was prepared for each of the seventy-four separate presentations for inclusion in DOE Energy Research Abstracts (ERA). (PMA)

A study was made to examine the effects which raising the ISA from 200 x 200 GeV to 400 x 400 GeV would have on the ''canonical'' experiments. These were ''canonical'' in the sense that they span the full range of foreseeable physics and have served as topics in previous Summer Studies and Workshops which resulted in quite explicit hardware designs and experimental goals. The study results indicate that all of the ''canonical'' experiments survive. Some are actually improved, some are unaffected, and some require changes which are suggested. In general, the 90/sup 0/ experiments are relatively unaffected. The single arm small angle spectrometer, the wide aperture (FATS-WASP) spectrometer and the Coulomb interference experiment have the largest number of modifications suggested. No uniqueness to these solutions are claimed, and there may be more desirable radical approaches. It is, however, felt that the 400 x 400 GeV ISA not only permits the work on conceptual experiments from previous Summer Studies to be taken over entirely, but indicates areas of improvement in many of them. Specifics of the individual experiments are discussed.

This Workshop was held concurrently with an IAEA Research Coordination Meeting on Exploration of the Possibility of High-LET Radiation for Non-conventional Radiotherapy in Cancer. The Workshop on Photon Activation Therapy (PAT) was given as a special session on April 18, as it was thoght PAT might eventually be found to be attractive to developing countries, which is a major concern of the IAEA. An effort was made to bring together representatives of the various groups known to be actively working on PAT; these included investigators from Sweden and Japan as well as the US. It is hoped that this compendium of papers will be of use to those currently active in this developing field, as well as to those who might join this area of endeavor in the future.

The sources of excess /sup 107/Ag observed in iron meteorites by Kaiser, Kelly, and Wasserburg (1980) are examined, with emphasis on the reactions of cosmic-ray particles with palladium. The cross sections for the production of the silver isotopes from palladium by energetic cosmic-ray particles are evaluated or estimated and used to calculate spallogenic production rates relative to that of /sup 53/Mn from iron. The upper limit for the production rate of excess /sup 107/Ag by galactic-cosmic-ray particles is 400 atoms/min/kg(Pd) which, over an exposure age of 10/sup 9/ years, would make only 1% of the observed excesses of /sup 107/Ag. Neutron-capture reactions with Pd isotopes produce mainly /sup 109/Ag. Binary fission of a siderophilic superheavy element would be expected to yield more /sup 109/Ag than /sup 107/Ag. An intense proton irradiation in the early solar system probably would produce a lower ratio of (/sup 107/Pd//sup 108/Pd) to (/sup 26/Al//sup 27/Al) than observed in meteorites. Therefore the presence of excess /sup 107/Ag in iron meteorites with large Pd/Ag ratios very likely is due to the incorporation of 6.5 x 10/sup 6/-year /sup 107/Pd of nucleosynthetic origin in these meteorites.

Preliminary design and performance test results for fast optical shutters intended for use in the Nova high power fusion laser system are briefly described. Both an opening shutter to protect the pellet target from amplified spontaneous emission (ASE), and a closing shutter to protect the laser from light reflected back from the target are discussed. Faraday rotators, synchronized by a 400 Hz oscillator, provide an opening shutter mechanism with an opening time of approximately 10 ..mu..s. A plasma closing shutter, employing electrical sublimation of a foil, provide a shutter closing time of 70 ns +- 20 ns. Energy for foil sublimation is provided by discharge of a 42 J capacitor bank. Implementation of these shutter techniques in the Nova system is anticipated to improve laser output power and efficiency. (RME)

A 25 megajoule, 20 kV capacitive energy storage and delivery system has been built and tested for Shiva--a 20 arm, 10 kJ, 20 TW neodymium glass fusion research laser. This system supplies over 3.5 megamperes to xenon flashlamps for optical pumping of the laser amplifier. About 15% of the energy is used to establish magnetic fields within Faraday rotator glass. A digital based control and diagnostics scheme is employed through the entire pulse power system. This scheme utilizes a distributed digital data bus that addresses every element through two levels of optical isolation. The interfacing of low level digital circuitry to a pulse power environment is discussed, as well as the design and performance of the total system. Cost and manufacturing details are important in a project of this size. The projected cost goal of 27 cents/joule, installed and operating, has been met. The general approach to the design, transient analysis, manufacture, and activation of this large power conditioning system is also discussed.

The absorption of intense laser light is found to be reduced when targets are irradiated by 1.06 ..mu..m light with long pulse widths (150-400 psec) and large focal spots (100-250 ..mu..m). Estimates of Brillouin scatter which account for the finite heat capacity of the underdense plasma predict this reduction. Spectra of the back reflected light show red shifts indicative of Brillouin scattering.

I see three main trends in the use of general purpose computers in real time. The first is more processing power. The second is the use of higher speed interconnects between computers (allowing more data to be delivered to the processors). The third is the use of larger programs running in the computers. Although there is still work that needs to be done, I believe that all indications are that the online need for general purpose computers should be available for the SCC and LHC machines. 2 figs.

There are many experimental elementary particle objectives which are uniquely achievable with polarized proton beams. These objectives require both higher beam energies and intensities than are presently available. The polarized ion source working group concluded that it looks quite practical to produce polarized H sources with output currents of several mA. The significance of this is best demonstrated by the fact that the ZGS operates at its space charge limit using a 6 mA H/sup -/ impolarized ion source and charge exchanger injection. Thus, polarized H/sup -/ ions offer the possibility of operating high energy synchrotrons at their ''normal'' intensity. With interesting physics to be done and the high probability of adequate intensities for both fixed target and colliding beam machines, the question to be answered is whether or not it is possible to accelerate polarized protons and/or deuterons to energies above the presently available 12 GeV/c of the ZGS and to store beams in a colliding beam machine such as the ISR or ISABELLE. This question was considered by the accelerator physics working group, and the conclusions reached are discussed.

To meet neutral-beam source requirements, a combination series switch/regulator system has been developed that can provide up to 40-kV at 80A output for 10-ms from the continuously decaying voltage of a charged capacitor bank. The system uses 100% feedback control of a series hard tube regulator. This feedback regulator is able to maintain a 40-kV output level for 100% load variations while the source voltage for the capacitor bank is drained from an initial 55-kV down to as low as 43-kV during a 10-ms pulse. In addition to controlling the output voltage, the series regulator tube also serves the dual role of a disconnect or interrupt switch at the end of each pulse and during the frequent occurrence of a neutral-beam source fault. In the interrupt mode, complete disconnect is achieved in less than 2-..mu..s after first observance of a fault condition; recovery times to normal operation of less than 10-..mu..s after fault clearance can be attained if desired.

Experimental data concerning S = O dibaryon resonances are reviewed, with an emphasis on the nucleon-nucelon system. Structures observed in the ..gamma..d channel, the ..pi..d elastic scattering, pp ..-->.. ..pi..d channel, and other channels are discussed. Experimental data are compared with various theories. The short-range forces can be represented by dibaryon resonances. Further measurements to clarify the understanding of dibaryons are also discussed. 53 refs., 24 figs.

We summarize simulations made by the Argonne/University of Illinois group using the Hybrid algorithm to include dynamical staggered fermions. Recent work on the mass spectrum and screening effects due to the inclusion of four light flavors of dynamical quarks is presented. We also present a brief overview of what we have learned about the finite temperature chiral phase transition. 5 refs., 4 figs., 1 tab.

LEED theory has developed to the point where the diffraction beam intensities can be computed using the locations of the surface atoms as the only adjustable parameters. The position of atoms in many clean monatomic solid surfaces and the surface structures of ordered monolayers of adsorbed atoms have been determined this way. Surface crystallography studies are now extended to small hydrocarbon molecules that are adsorbed on metal surfaces. These studies are reviewed. (GHT)

When the plasma outflow velocity relative to the critical surface is supersonic, compressional density profiles can form in the critical region. These compressions involve dissipative processes like those in collisionless shocks; associated plasma instabilities and reflected ions may inhibit energy transport and enhance laser light absorption.

The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs with condensed hydrogen while pumping mixtures of both. A solution to this problem is a compound design whereby the first stage condenses the hydrogen and the second, or sorption, stage pumps the helium. The TSTA pump designed at Lawrence Livermore National Laboratory uses argon gas to cryotrap the helium in the helium-hydrogen mixture. The argon is sprayed directly onto the 4.2 K surface at a rate proportional to the helium flow rate, permitting continuous pumping of the helium-hydrogen mixtures in a single-stage pump. However, the possibility of differential desorption as a first stage in the TSTA gas separation cycle required the inclusion of a first-stage hydrogen isotope condenser. The design, performance, and operating characteristics are discussed.

A calculation is presented for the final bunching of a particle beam in a synchrotron or storage ring. The voltage per turn, the harmonic number, and the bunching time are obtained. (PMA)

The Electromagnetic Isotope Enrichment Facility (EMIEF) is currently used to produce 225 enriched stable isotopes of 50 elements. Among these are included most of the known elements with stable isotopes except for the noble gases, certain light elements, monisotopic elements, etc. The EMIEF can also be used to produce enriched samples of radioactive species, most notably the isotopes of uranium and plutonium. These enriched materials are placed in either the Sales Inventory of in the Research Materials Collection (RMC). The materials in the Sales Inventory are for sale to anyone on a first come, first served basis. Prices in the most recent catalog range from $0.05/mg for 99.8% /sup 140/Ce to $1,267/mg for 98.5% /sup 176/Lu. The materials in the RMC are made available to US researchers (or groups that include a US investigator) on a loan basis for use in non-destructive experiments and applications. In addition, certain samples have been provided to European investigators for cross-section studies through the auspices of EURATOM and the European-American Nuclear Data Committee. The status of the enriched isotopes included in the Sales Inventory is tabulated where isotopes are listed that are either not available or are in insufficient quantity or quality to meet …

A Co-57 based XRFA system has been installed on-line at ICPP to monitor uranium concentrations after first cycle decontamination. A small, medium, or large collimator is used to restrict fission product (fp) background count rates. Using two 50 mCi sources, 1 gU/1 can be measured to +-2% in 10 min with the medium collimator. A computer-based MCA runs the system automatically, controls an insertable U foil (allows calibration anytime) and an automatic W shutter (permits removal of fp background); prints hourly mean U concentrations and a daily log of past 24-h means. Co-57 sources are changed annually in 1 min without disassembly of a lead-steel enclosure that surrounds the de-entrainment tank and XRFA assembly.

Article commenting on a previously published article, "Study of molecular interaction in binary liquid mixtures of ethyl acetoacetate with chloroform and dimethylsulphoxide using excess acoustic parameters and spectroscopic methods."

Article on the use of genetics for the management of a recovering population and a temporal assessment of migratory peregrine falcons in North America.

Optical coatings are used in lasers systems for fusion research to control beam propagation and reduce surface reflection losses. The performance of coatings is important in the design, reliability, energy output, and cost of the laser systems. Significant developments in coating technology are required for future lasers for fusion research and eventual power reactors.

The history of the magnetic-mirror approach to a fusion reactor is primarily the history of our understanding and control of several crucial physics issues, coupled with progress in the technology of heating and confining a reacting plasma. The basic requirement of an MHD-stable plasma equilibrium was achieved following the early introduction of minimum-B multipolar magnetic fields. In refined form, the same magnetic-well principle carries over to our present experiments and to reactor designs. The higher frequency microinstabilities, arising from the non-Maxwellian particle distributions inherent in mirror machines, have gradually come under control as theoretical prescriptions for distribution functions have been applied in the experiments. Even with stability, the classical plasma leakage through the mirrors posed a serious question for reactor viability until the principle of electrostatic axial stoppering was applied in the tandem mirror configuration. Experiments to test this principle successfully demonstrated the substantial improvement in confinement predicted. Concurrent with advances in mirror plasma physics, development of both high-power neutral beam injectors and high-speed vacuum pumping techniques has played a crucial role in ongoing experiments. Together with superconducting magnets, cryogenic pumping, and high-power radiofrequency heating, these technologies have evolved to a level that extrapolates readily to meet the requirements of …

Symmetric impact shock Hugoniot measurements have been made on Ta with an electrically exploded foil gun system. The results obtained to date for the Hugoniot of Ta cover the range 0.19 to 0.78 TPa (impact velocities from 4.0 to 9.7 km/s) and agree with data obtained by other researchers to within 2.7% rms. Recent improvements in the system include electromagnetic shielding of impactor and target, continuous measurement of impactor velocity with a Fabry-Perot interferometer and computer-aided analysis of shot film. Conservative extrapolation from current operating conditions indicate that pressures of 1.1 to 1.5 TPa could be achieved with little difficulty.