The forward-backward asymmetry A expected from the ..gamma.. - Z/sup 0/ interference term in the process e/sup +/e/sup -/ ..-->.. q anti q is observed in the lab production angular distribution of high momentum A baryons. The data were collected with the High Resolution Spectrometer at PEP and an integrated luminosity of 256 pb/sup -1/ at ..sqrt..s = 29 GeV was used in the analysis. The asymmetry is seen to increase with the fractional energy z = 2E/..sqrt..s of the A due to the decreasing presence of nonleading particles. The value obtained for A baryons with z greater than or equal to 0.3 is A = -0.22 +- 0.08 +- 0.02.

This paper presents measurements of the inclusive production cross sections of ..lambda.. baryons in e/sup +/e/sup -/ annihilations at ..sqrt..s = 29 GeV. The data sample corresponds to an integrated luminosity of 256 pb/sup -1/ collected with the High Resolution Spectrometer at PEP. Comparisons are made to the predictions of the Lund model. The data are well described using a strange diquark suppression parameter, (us/ud)/(s/d), of 0.89 +- 0.10/sub -0.16//sup +0.56/, and the measured ..lambda../sub c/ ..-->.. ..lambda.. + X branching ratio of 23 +- 10%. No polarization is observed in the ..lambda.. decays. 17 refs., 5 figs.

The shower counter system of the SLAC-LBL Mark II detector is a large lead/liquid argon system of the type pioneered by Willis and Radekal; however, it differs in most details and is much larger than other such detectors currently in operation, It contains, for example, 8000 liters of liquid argon and 3000 channels of low noise electronics, which is about eight times the size of the system of Willis et al. in the CERN ISR. This paper reports, with little reference to design, on the operation and performance of the Mark II system during approximately a year and a half of operation at the Stanford Linear Accelerator Center's e{sup +}-e{sup -} facility, SPEAR. The design and construction of the system have previously been described and a detailed discussion of all aspects -- design, construction, operation, and performance -- is in preparation.

We present a study of the decay properties of charmed D mesons produced near the peak of the {psi}" (3770) resonance in e{sup +}e{sup -} annihilation. Branching fractions for nine Cabibbo-favored and three Cabibbo-suppressed decay modes are presented along with upper limits on one additional Cabibbo-favored and four additional Cabibbo-suppressed decay modes. A study of K{pi}{pi} decay mode Dalitz plots reveals a large quasi-two-body pseudoscalar-vector component for the D{sup 0} decays and an apparent nonuniform population an the Dalitz plot for the D{sup +} decay into K{sup -}{pi}{sup +}{pi}{sup +}. Using tagged events, we measure the charged particle multiplicity and strange particle content of D decays. A measurement of the D{sup +} and D{sup 0} semileptonic decay fractions indicates that the D{sup +} has a significantly longer lifetime than the D{sup 0}.

The oxidation behavior of type 316 stainless steel and candidate advanced alloys for the gas-cooled fast reactor (GCFR) is being investigated at General Atomic Company. The test program consists of oxidation tests in prototypic GCFR environments. Two tests have been completed to date and a third test is under way. The first test was performed in an environment containing a hydrogen/water ratio of 10. The oxidation behavior of all the alloys was good to excellent in this environment. Preferential oxidation of chromium was responsible for this behavior. The second test was performed in an environment containing a hydrogen/water ratio of 0.25, where both chromium and iron oxides are thermodynamically stable. Some of the alloys and some of the ribbed type 316 stainless steel test specimens showed unacceptable oxidation resistance in this environment. In the third test, presently under way, two different pretreatment procedures are being used to control the poor oxidation behavior observed in the second test. Early results show some degree of success.

A new software trigger scheme has been developed to augment and enhance the existing charged and neutral triggers by providing sensitivity to new event topologies and some level of control over accelerator-induced backgrounds. Historically, the Mark II existed with two primary trigger components: a charged track finder based upon the central and vertex drift chambers and the time-of-flight counters; and an electromagnetic trigger based upon the total energy deposited in each of ten calorimeter modules. The trigger component of the new system is based upon the Mark II electromagnetic calorimetry but with significantly increased granularity and the inherent flexibility of software. Trigger processing also benefits from the relatively long period of time (up to 8.3 ms) between SLC beam crossings. The production of long-lived neutral particles provides an example of an event topology which would not have triggered in the old system. By decaying beyond the first few drift chamber layers, such particles avoid the charged particle trigger, yet could produce clear signals in the calorimeters. Another example is the class of events containing a single photon as the visible particle such as occur in the reaction e{sup +}e{sup -} {yields} Z{sup 0}{gamma} {yields} {nu}{nu}{gamma}. Sensitivity to this reaction is …

This paper covers RF power sources for accelerator applications. The approach has been with particular customers in mind. These customers are high energy physicists who use accelerators as experimental tools in the study of the nucleus of the atom, and synchrotron light sources derived from electron or positron storage rings. This paper is confined to electron-positron linear accelerators since the RF sources have always defined what is possible to achieve with these accelerators. 11 refs., 13 figs.

Present experiments on TMX-U and modeling of MFTF-B indicate that plasma-surface interactions can be controlled in MFTF-B. The MFTF-B configuration uses a hot electron population created by ECRH and a sloshing-ion population created by neutral beams in the thermal barrier region to create a potential that confines the central cell ions. Neutral beams and ICRH are used to heat the central cell ions. Plasma-surface interactions can be minimized at radial surfaces by control of the axial confinement of the edge plasma. The thermal barrier configuration is sensitive to the background neutral density, and requires low wall reflux and efficient shielding by the edge plasma. Glow discharge cleaning, titanium gettering, and control of the gas from neutral beams will be used to provide wall conditioning and to reduce the background gas pressure. The shielding efficiency of the plasma edge has been modeled in MFTF-B by comparing computer codes with current experimental measurements. In addition, it is very important to reduce high-energy neutral-beam-injected impurities; this is accomplished by using gettering or magnetic separation in the injector systems. Plasma-edge scrapers, diverter-like devices, and direct-conversion equipment will be located in the end region. Major disruptions are not anticipated. Finally, MFTF-B will also test some …

Curtailment planning at a generally rudimentary level has been undertaken by the governments of some twenty states. Many utilities have demand-curtailment plans, however, these are often incorporated in plans for meeting capacity shortages. In at least five states, there are apparently no curtailment plans either at the state-government level or at the utility level. Moreover, none of the existing electricity demand curtailment plans examined included an explicit statement of the planners' objective in arriving at a specified sharing of the burdens of curtailment among consumer classes. Yet clearly the actual allocations of such burdens will affect the cost of the shortage. Since a study of state planning failed to yield a clear-cut indication of which of many possible curtailment allocation schemes would best serve as a point of departure for the design of an optimal curtailment strategy to deal with prolonged supply deficiencies, it was then decided to use a linear-programming approach. The advantages of such an approach are examined first, after which some important conceptual and practical problems in the design of a specific linear-programming model are addressed. A mathematical statement of the model is then followed by a brief review the principal methodological shortcomings of the linear-programming approach. …

A Workshop on Program Options in Intermediate-Energy Physics sponsored by the US Department of Energy was held at Los Alamos Scientific Laboratory, August 20 to 31, 1979. The scope of the workshop included all laboratories in intermediate-energy physics, worldwide, and all of these sent representatives to the workshop. The workshop addressed itself to the critical questions on nuclear and particle physics and how they can best be investigated by intermediate-energy accelerators. Among the questions that the workshop members considered were: (1) what are the important physics topics which might be understood through research on these accelerators in the next 10 years. These topics include, but are not restricted to, fundamental interactions and symmetries in particle physics, and nuclear modes of motion, structure, and reaction mechanisms; (2) what experiments should be undertaken to carry out the program. What are the kinematical conditions, accuracies, resolutions, and other parameters required to obtain the desired knowledge; (3) which accelerators are best suited for each experiment. What work at other laboratories (low-, intermediate-, or high-energy) could be undertaken to complement and/or supplement the proposed LAMPF program; and (4) what new facility capabilities should be explored for the long-term future. The workshop was divided into small …

Beams of unstable nuclei can be formed by direct injection of the radioactive atoms into an ion source, or by using the momentum of the primary production beam as the basis for the secondary beam. The effectiveness of this latter mechanism in secondary beam formation, i.e., the quality of the emerging beam (emittance, intensity, energy spread), depends critically on the nuclear reaction kinematics, and on the magnitude of the incident beam energy. When this beam energy significantly exceeds the energies typical of the nuclear reaction process, many of the qualities of the incident beam can be passed on to the secondary beam. Factors affecting secondary beam quality are discussed, along with techniques for isolating and purifying a specific secondary product. The ongoing radioactive beam program at the Bevalac is used as an example, with applications, present performance and plans for improvements.

The usefulness of x-ray absorption spectroscopy in studies of electronic structure in materials is discussed. 7 refs., 4 figs. (CBS)

Thermal damage to susceptible material in accessible regions of the reactor building was distributed in non-uniform patterns. No clear explanation for non-uniformity was found in examined evidence, e.g., burned materials were adjacent to materials that appear similar but were not burned. Because these items were in proximity to vertical openings that extend the height of the reactor building, we assume the unburned materials preferentially absorbed water vapor during periods of high, local steam concentration. Simple hydrogen-fire-exposure tests and heat transfer calculations duplicate the degree of damage found on inspected materials from the containment building. These data support estimated 8% pre-fire hydrogen concentration predictions based on various hydrogen production mechanisms.

New hydride derivatives of thorium (IV) and uranium (IV), HM[N(SiMe{sub 3}){sub 2}]{sub 3}, have recently been prepared. This paper describes the crystal structure of the uranium species, though the hydride-ion was not located, and shows that the thorium analogue is isostructural. The reaction chemistry and spectroscopy leave no doubt that these derivatives are authentic examples of four-coordinate, monomeric hydride, compounds.

Experimental and theoretical studies of field reversal in a mirror machine are reported. Plasma-gun experiments demonstrate that reversed-field plasma layers are formed. Low energy plasma flowing behind the initially produced plasma front prevents tearing of the layer from the gun muzzle. MHD simulation shows that tearing can be obtained by impeding the slow plasma flow with a plasma divider. It is demonstrated theoretically that a field-reversed mirror imbedded in a multipole field can be sustained in steady state with neutral-beam injection even in the absence of impurities. MHD stability analysis shows that growth rates of elongated reversed-field theta-pinch configurations decrease with axial extension, which indicates the importance of including finite Larmor radius in the analysis. Tilting-mode criteria are dramatically improved by proper shaping, and a problimak shape is proposed. Tearing mode stability of reversed-field theta-pinches is greatly enhanced by flux exclusion. Self-consistent, 1-1/2-dimensional transport codes have been developed, and initial results are presented.

The Transverse Field Focusing (TFF) system described here is a prototype for a negative-ion based neutral beam line with possible applications in the US magnetic fusion energy program. The prototype system consists of four main modules: (1) H/sup -/ source, (2) 80 keV pre-accelerator, (3) TFF matching/pumping (M/P) section, and (4) 180 keV TFF accelerator. The first three modules have been installed on the beam line, with the fourth to follow soon. The crucial module, invoking the most difficult (and interesting) physics and engineering issues, is the M/P section. It performs: (a) gas removal from the beam by differential pumping, (b) electron removal, (c) beam thickness reduction to match the TFF accelerator parameters, and (d) beam-edge confinement. The four beamline modules are discussed in this survey, with emphasis on design features of the M/P section. 17 refs., 4 figs.

The structural arrangement of a hydrated glass surface depends on the composition, thermal history and surface treatment. This paper considers the surface treatment of a lead glass with weak and strong acid solutions and in particular hydrogen peroxide, to give a microscopically clean microsphere.

An injector system has been designed to provide a fully stripped oxygen beam for acceleration in the CERN PS complex. An ECR source will provide an O/sup 6/+ beam to a heavy ion RFQ accelerator. The beam from the RFQ will be further accelerated by the CERN Linac 1 (Old Linac) in the 2 ..beta.. lambda-mode to an energy of 12.5 MeV/u at which point it will be fully stripped for subsequent acceleration in the CERN synchrotrons. The specifications of the new equipment and modifications to the existing linear accelerator are described.

The RING power system described in this paper is proposed as a primary or emergency heat rejection system for advanced space reactor power applications. The system employs a set of four (4) counter-rotating, 90 degree offset, coolant-carrying rings. The rings (segmented, corrugated, finned, thin-walled pipes, filled with liquid lithium) pass through a cavity heat exchanger and reradiate the absorbed heat to the space environment. 25 refs., 6 figs., 3 tabs.

The use of ion beam and pulsed laser processing is reviewed for the near-surface modification of a wide range of materials. The techniques of ion implantation doping, ion beam and laser mixing, and pulsed-laser annealing are stressed with particular emphasis on the nonequilibrium aspects of these processing techniques and on new materials properties which can result. Examples are presented illustrating the utility of these techniques for fundamental materials research as well as practical surface modifications.

ATLAS, the Argonne Tandem-Linac Accelerator System, is a project to upgrade the existing Argonne superconducting linac heavy-ion booster which began providing beams of heavy-ions for experimental nuclear research in 1979. When completed ATLAS will provide beams of heavy ions up to approximately mass 130 at energies as high as 25 MeV/A. The construction of ATLAS is approximately 60% complete. First beam from the accelerator is expected in spring of 1985.

The Photovoltaic Advanced Silicon (PVAS) Branch at the Solar Energy Research Institute (SERI) has initiated a comparative study to assess the potential of MIS-type solar cells for low-cost terrestrial photovoltaic systems in terms of performance, stability, and cost-effectiveness. Several types of MIS and SIS solar cells are included in the matrix study currently underway. This approach compares the results of MIS and p/n junction solar cells on essentially identical thin-film polycrystalline silicon materials. All cell measurements and characterizations are performed using uniform testing procedures developed in the Photovoltaic Measurements and Evaluation (PV M and E) Laboratory at SERI. Some preliminary data on the different cell structures on thin-film epitaxial silicon on metallurgical-grade substrates are presented here.

The deep inelastic electron scattering cross sections per nucleon sigma/sub A/ for d, He, Be, C, Al, Ca, Fe, Ag, and Au were measured in kinematic range 0.09 less than or equal to x less than or equal to 0.9 and 2 less than or equal to Q/sup 2/ less than or equal to 15 (GeV/c)/sup 2/ using electrons with energies ranging from 8 to 24.5 GeV. The ratio sigma/sub A//sigma/sub d/ is consistent with unity in the range 0.1 < x < 0.3. For 0.3 < x < 0.8, the ratio decreases logarithmically with atomic weight A, or linearly with average nuclear density. No Q/sup 2/ dependence in the ratio was observed over the kinematic range of the data. This has been interpreted as evidence for a change in the quark momentum distribution in the nucleus due to the presence of 6 quark clusters or a larger nucleon bag size. 13 references.

The Workshop on Electronuclear Physics with Internal Targets was held at SLAC on January 5-8, 1987. The idea for this workshop grew out of interest among physicists at SLAC and MIT/Bates who have been exploring the possibilities for internal targets in the PEP ring at SLAC and in a proposed stretcher ring at MIT/Bates. The aim of the workshop was to bring together physicists from these groups and from other laboratories and universities to discuss the new physics that could be made accessible with internal targets, and to share information on recent developments in internal target technology, on the impact of internal targets on ring operation, and on the detector requirements. The workshop was sponsored by NPAS, the program of Nuclear Physics at SLAC, and it was attended by more than 100 physicists from the US, Canada, Europe, and Japan. The workshop sessions began with two days of invited talks followed by two days of shorter presentations organized by the chairmen of four Working Groups. Written versions of all the plenary talks and all but four of the Working Group talks are presented here.