Heavy beam loading in the PEP-II B Factory along with large ring circumferences places unique requirements upon the low-level rf (LLRF) system. RF feedback loops must reduce the impedance observed by the beam while ignoring the cavity transients caused by the ion clearing gap. Special attention must be placed on the cavity tuner loops to allow matching the ion clearing gap transients in the high energy ring and the low energy ring. A wideband fiber optic connection to the longitudinal feedback system allows a rf station to operate as a powerful ''sub-woofer'' to damp residual low order coupled bunch motion. This paper describes the design and performance of the VXI based, EPICS controlled, PEP-II low-level rf system(s). Baseband in-phase and quadrature (IQ) signal processing using both analog and modern digital techniques are used throughout the system. A family of digital down converters provide extremely accurate measurements of many rf signals throughout the system. Each system incorporates a built-in network analyzer and arbitrary rf function generator which interface with Matlab to provide a wide range of functions ranging from automated configuration of each feedback loop to cavity FM processing. EPICS based sequences make the entire system a turn-key operation requiring minimal …

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During the tenure of the DOE grant DE-FG05-87EI145316 we have concentrated on equilibrium geometries, stability, and the electronic structure of transition metal-carbon clusters (met-cars), clusters designed to mimic the chemistry of atoms, and reactivity of homo-nuclear metal clusters and ions with various reactant molecules. It is difficult to describe all the research the authors have accomplished as they have published 38 papers. In this report, they outline briefly the salient features of their work on the following topics: (1) Designer Clusters: Building Blocks for a New Class of Solids; (2) Atomic Structure, Stability, and Electronic Properties of Metallo-Carbohedrenes; (3) Reactivity of Metal Clusters with H{sub 2} and NO; and (4) Anomalous Spectroscopy of Li{sub 4} Clusters.

The missions of the U.S. Department of Energy's Richland Operations Office (DOE/RL) are to safely manage the Hanford Site, to manage and clean up its legacy wastes, and to develop and deploy new science and technology in the environmental and energy fields. Collectively, DOE/RL and its contractors are the most important single entity in the Tri-Cities local economy (Pasco, Kennewick, and Richland, Washington, and the surrounding area). Although the relevant economic region affected by DOE/RL and its contractors actually embraces a geographic area reaching from Yakima in the west to Walla Walla in the east and from Moses Lake in the north to Pendleton, Oregon, in the south, over 90% of economic impacts likely occur in Benton and Franklin Counties. These two counties are defined as the ''local'' Tri-Cities economy for purposes of this study (see Figure 1). In the federal fiscal year (IV) 1998 (October 1, 1997 through September 30, 1998), the total impact of DOEs local $1.6 billion budget was felt through payrolls of $519 million and local purchases of goods and services of $246 million. The total local spending of $765 million was down slightly from the FY 1997 total of $774 million. Taking into account the …

The results of this study establish a framework for evaluation of the cost impact of many performance parameters in coated conductor manufacturing systems. Since the cost and concepts are based on early developmental results and engineering judgment, the study should be updated periodically based on latest data to enhance its usefulness. The study should be expanded to include other promising processes under consideration or development for manufacture of coated conductors. Review of this study by as wide a group of experts from industry, national laboratories and universities as possible is desirable to facilitate improving accuracy of the estimates and communication on the issues involved. The results for the case of achieving the $10/kA-m goal at a J{sub c} of 10{sup 5} a/cm{sup 2} applicable to applications requiring a magnetic field perpendicular to the direction of current flow may be viewed as somewhat discouraging. However, there is ample margin for improvement due to continued development and engineering that could enable meeting the goal of $10/kA-m.

In linacs with high single-bunch charge, and tight tolerances for energy spread and emittance growth, controlling the short-range wakefield effects becomes extremely important. The effects of the wakefields, in turn, depend on the bunch length and also on the bunch shape. It was shown in the linac of the Stanford Linear Collider (SLC), for example, that by shaping the bunch, the final rms energy spread could be greatly reduced, compared to for the standard Gaussian bunch shape[1]. Therefore, in machines with high single-bunch charge, a method of measuring bunch shape can be an important beam diagnostic. In a linac with low single-bunch charge, the longitudinal bunch shape can be obtained relatively easily from a single measurement of the beam's final energy spectrum, provided that the final to initial energy ratio is large. One merely shifts the average phase of the beam, so that it rides off-crest sufficiently to induce an energy variation that is monotonic with longitudinal position. Then, by knowing the initial and final energies, the rf wave number, and the average beam phase, one can directly map the spectrum into the bunch shape. In a linac with high single-bunch charge, however, due to the effect of the longitudinal …

This is the final progress report for the experimental nuclear physics program at Georgia State University (GSU) under the leadership of Gus Petitt. In June, 1996, Professor Petitt retired for health reasons and the DOE contract was extended for another year to enable the group to continue it's work. This year has been a productive one. The group has been heavily involved in the E866 experiment at Fermilab where we have taken on the responsibility of developing a new level-3 trigger for the experiment. Bill Lee, the graduate student in our group expects to obtain his thesis data from the run extension currently in progress, which focuses on the A dependence of J/{psi}'s and {Upsilon}'s from beryllium, tungsten, and iron targets. In the past year and a half the GSU group has led the development of a new level-3 software trigger system for E866. Our work on this project is described.