We study single bunch stability with respect to monopole longitudinal oscillations in electron storage rings. Our analysis is different from the standard approach based on the linearized Vlasov equation. Rather, we reduce the full nonlinear Fokker-Planck equation to a Schroedinger-like equation which is subsequently analyzed by perturbation theory. We show that the Haissinski solution [3] may become unstable with respect to monopole oscillations and derive a stability criterion in terms of the ring impedance. We then discuss this criterion and apply it to a broad band resonator impedance model.

On June 6, 1995, a waiver to Hanford Site Solid Waste Acceptance Criteria, was approved by the US Department of Energy Richland Operations Office (RL) to replace the low-level, mixed, and transuranic (TRU) generator assessment programs with the Solid Waste Assurance Program (SWAP). This is associated with a waiver that was approved on March 16, 1995 to replace the Storage/Disposal Approval Record (SDAR) requirements with the Waste Specification System (WSS). This implementation plan and the SWAP applies to Solid Waste Disposal (SWD) functions, facilities, and personnel who perform waste acceptance, verification, receipt, and management functions of dangerous, radioactive, and mixed waste from on- and off-site generators who ship to or within the Hanford Site for treatment, storage, and/or disposal (TSD) at SWD TSD facilities.

Arkani-Hamed, Dimopoulos and Dvali have recently proposed that gravity may become strong at energies near 1 TeV thus removing the hierarchy problem. This scenario can be tested in several ways at present and future colliders. In this paper we examine the exchange of towers of Kaluza-Klein gravitons and their influence on the production of pairs of massive gauge bosons in {gamma}{gamma} collisions. These tower exchanges are shown to lead to a new dimension-8 operator that can significant alter the Standard Model expectations for these processes. The role of polarization for both the initial state photons and the final state gauge bosons in improving sensitivity to graviton exchange is emphasized. We find that the discovery reach for graviton tower exchange in the {gamma}{gamma} {r_arrow} W{sup +}W{sup {minus}} channel to be significantly greater than for any other process so far examined.

Analysis of directed flow observable for protons and pions from Au+Au collisions at 10.8 GeV/nucleon from experiment E917 at the AGS is presented. Using a Fourier series expansion, the first Fourier component, {nu}{sub 1},was extracted as a function of rapidity for mid-central collisions (17-24%). Clear evidence for positive directed flow is found in the proton data, and a weak, possibly negative directed flow signal is observed for {pi}{sup +} and {pi}{sup {minus}}.

Normal form analysis and tracking results show that both normal and skew resonances are driven strongly by the nonlinear fields of the IR quadrupoles. We report here on the possibility of improving the dynamic aperture by compensating these resonances with the use of correctors placed in the IRs. The effectiveness of local correction schemes in the presence of beam-beam interactions is also studied.

We report a novel sol-gel dip-coating process to form dual-layer microporous silica membranes with improved membrane performance and reproducibility. First, we deposit a surfactant-templated silica (STS) intermediate layer on top of a commercial {gamma}-alumina support both to improve its ''surface finish'' and to prevent a subsequently deposited microporous overlayer from penetrating into the support. Second, membranes are processed under clean room conditions to avoid dust contamination and, third, membranes are vacuum-calcined to promote further pore shrinkage and impart surface hydrophobicity. The resulting asymmetric membrane exhibits a gradual change in pore diameter from 50{angstrom} ({gamma}-alumina support layer) to 10-12{angstrom} (STS intermediate layer), and then to 3-4{angstrom} (30nm thick, ultramicroporous silica top-layer). Compared to a single-layer process using only the microporous overlayer, the dual-layer process improves both flux and selectivity. For the industrially important problem of natural gas purification, the combined CO{sub 2} flux [(3{approx} 0.5) x 10{sup {minus}4} cm{sup 3}(STP)/(s{center_dot}cm{sup 2}{center_dot}cm-Hg)] and CO{sub 2}/CH{sub 4} separation factors [200{approx}600] are superior to all previously reported values for separation of a 50/50 (v/v) CO{sub 2}/CH{sub 4} gas mixture. In addition, the membrane selectively separated hydrogen from a simulated reformate from partial oxidation of methanol as evidenced by a high concentration of hydrogen recovery.

{sup 13}C-enriched polyethylene was subjected to {gamma}-irradiation in the presence of air at 25 and 80 C for total doses ranging from 71 to 355 kGy. Significant quantities of hydroperoxides were detected in the 25 C irradiated sample by {sup 13}C magic angle spinning NMR spectroscopy. This method of detection was performed on the solid polymer and required no chemical derivatization or addition of solvent. The chemical stability and subsequent products of the hydroperoxide species were studied by annealing the irradiated samples in air at temperatures ranging from 22 to 110 C. A time-temperature superposition analysis provided an activation energy of 108 kJ/mol for the hydroperoxide decomposition process. The primary products of hydroperoxide decomposition were ketones and secondary alcohols with lesser amounts of acids and esters. EPR measurements suggest that the reactive hydroperoxide species reside in the amorphous phase of polyethylene, consistent with degradation occurring in the amorphous phase.

A brief historical perspective covering the most mature chemically-based metal ion separation methods is presented, as is a summary of the recommendations made in the 1987 National Research Council (NRC) report entitled ''Separation and Purification: Critical Needs and Opportunities''. A review of Progress in Metal Ion Separation and Preconcentration shows that advances are occurring in each area of need cited by the NRC. Following an explanation of the objectives and general organization of this book, the contents of each chapter are briefly summarized and some future research opportunities in metal ion separations are presented.

Argonne National Laboratory is developing a ceramic waste form to immobilize salt containing fission products and transuranic elements. Preliminary results have been presented for ceramic waste forms containing surrogate fission products such as cesium and the lanthanides. In this work results from scanning electron microscopy/energy dispersive spectroscopy and x-ray diffraction are presented in greater detail for ceramic waste forms containing surrogate fission products. Additionally, results for waste forms containing plutonium and surrogate fission products are presented. Most of the surrogate fission products appear to be silicates or aluminosilicates whereas the plutonium is usually found in an oxide form. There is also evidence for the presence of plutonium within the sodalite phase although the chemical speciation of the plutonium is not known.

None

The shock sensitivity of a pressed solid explosive formulation, LX-19, containing 95.2% by weight epsilon phase 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (HNIW) and 4.8% Estane binder, was determined using the wedge test and embedded manganin pressure gauge techniques. This formulation was shown to be slightly more sensitive than LX-14, which contains 95.5% HMX and 4.5% Estane binder. The measured pressure histories for LX-19 were very similar to those obtained using several HMX-inert binder formulations. An Ignition and Growth reactive model for LX-19 was developed which differed from those for HMX-inert binder formulations only by a 25% higher hot spot growth rate.

In this work we explore the possibility of achieving bulk electrical properties in single layer sputter deposited films grown epitaxially on (111) oriented BaF{sub 2} substrates. There are a number of sputter deposition parameters that can be varied in order to optimize the film quality. It is important to understand the effect of varying the deposition temperature, Ar sputtering gas pressure, and the substrate bias. We will consider only Bi and Bi{sub 0.86}Sb{sub 0.14} films in this paper. These materials were chosen since they have the same simple structure, two different band gaps and do not change significantly either in physical or electrical properties with small amounts of cross contamination. We will also present our work on multilayer thermoelectrics made of Bi and Bi{sub 0.86}Sb{sub 0.14} layers. There has been considerable interest in this multilayer structure in the literature. Theoretical calculations of the band structure and interface states of these multilayer structures have been made by Mustafaev and Agassi et al. respectively [6,7]. Experimentally Yoshida et al. have examined similar multilayer structures grown by MBE as well as Bi/Sb multilayer samples in which report an anomalous thermoelectric power [8].

The goal of the U.S. Department of Energy (DOE) Wind Energy Program's wind resource assessment group located at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, is to improve the characterization of the wind resource in many regions of the world in support of the U.S. wind energy industry. NREL characterizes the level of the available wind resource at wind turbine hub heights (typically 30 m to 50 m above ground level) using wind power density, expressed in units of Watts per square meter. Wind power density values are frequently used to classify the wind resource level with the higher wind power classes assigned to areas with high power density values. NREL has developed a wind assessment methodology to produce wind resource maps useful for wind prospecting and wind energy project implementation. The methodology integrates information from global climatic data sets and also involves a critical meteorologic analysis of the climatic data. It is in the context of the critical meteorological analysis and the automated mapping system that we plan to evaluate the usefulness of Reanalysis data for wind assessment purposes.

Preliminary results from the postirradiation examinations of microplates irradiated in the RERTR-1 and -2 experiments in the ATR have shown several binary and ternary U-MO alloys to be promising candidates for use in aluminum-based dispersion fuels with uranium densities up to 8 to 9 g/cm{sup 3}. Ternary alloys of uranium, niobium, and zirconium performed poorly, however, both in terms of fuel/matrix reaction and fission-gas-bubble behavior, and have been dropped from further study. Since irradiation temperatures achieved in the present experiments (approximately 70 C) are considerably lower than might be experienced in a high-performance reactor, a new experiment is being planned with beginning-of-cycle temperatures greater than 200 C in 8-g U/cm{sup 3} fuel.

An Ar-40/Ar-39 and U-Pb study was performed of the Geysers plutonic complex of the Geysers Geothermal Field in California. Sixty-nine ion microprobe spot analyses of zircons from four granite samples from the plutonic complex that underlies the Geysers geothermal field yielded Pb-207/Pb-206 vs. U-238/Pb-206 concordia ages ranging from 1.13 {+-} 0.04 Ma to 1.25 {+-} 0.04 Ma. The U-Pb ages coincide closely with Ar-40/Ar-39 age spectrum plateau and ''terminal'' ages from coexisting K-feldspars and with the eruption ages of overlying volcanic rocks. The data indicate that the granite crystallized at 1.18 Ma and had cooled below 350 C by {approximately}0.9-1.0 Ma. Interpretation of the feldspar Ar-40/Ar-39 age data using multi-diffusion domain theory indicates that post-emplacement rapid cooling was succeeded either by slower cooling from 350-300 C between 1.0 and 0.4 Ma or transitory reheating to 300-350 C at about 0.4-0.6 Ma. Heat flow calculations constrained with K-feldspar thermal histories and the pre sent elevated regional heal flow anomaly demonstrate that appreciable heat input from sources external to the known Geysers plutonic complex is required to maintain the geothermal system. This requirement is satisfied by either a large, underlying, convecting magma chamber (now solidified) emplaced at 1.2 Ma or episodic intrusion …

Nearly half of the US utility-owned steam electric generating capacity is cooled by once-through cooling systems. These plants withdraw cooling water primarily from surface water bodies. Section 316(b) of the Clean Water Act requires that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available (BTA) for minimizing adverse environmental impacts. At present, the US Environmental Protection Agency (EPA) has not yet promulgated applicable implementing regulations governing intake structures; however, the Agency is required by a Consent Decree to develop such regulations. EPA has presented a draft tiered regulatory framework approach that, depending on site-specific factors, may impose various regulatory burdens on affected utilities. Potential new requirements could range from compiling and submitting existing data to demonstrate that existing conditions at each unit represent BTA to retrofitting plants with closed-cycle cooling systems (primarily cooling towers). If the final regulations require installation of cooling towers or implementation of other costly plant modifications, utilities may elect to close some generating units rather than invest the finds necessary to upgrade them to meet the Section 316(b) requirements. Potentially, some regions of the country may then have a higher proportion of closed units than others, leading to a …

As part of an effort to fabricate oxide-based fibrous monolithic ceramics, sintering of mullite has been examined. The effects of Y{sub 2}O{sub 3} additions on sinterability of sol-gel-derived mullite and on the resulting microstructure were evaluated over a range of compositions, sintering times, and temperatures. Electron microscopy, X-ray diffraction, differential thermal analysis, and density measurements indicated that the Y{sub 2}O{sub 3} additions promoted densification through formation of a Y-Si-Al-O liquid phase. This phase tended to solidify as a glass during normal processing, but could be crystallized by a two-step annealing process at 1300 and 1200 C. The four-point flexural strengths of mullite and mullite-5 Wt.% Y{sub 2}O{sub 3} were also examined.

The next generation of radiographic machines based on induction accelerators require very high brightness electron beams to realize the desired x-ray spot size and intensity. This high brightness must be maintained throughout the beam transport, from source to x-ray converter target. The accelerator for the second-axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility is being designed to accelerate a 4-kA, 2-{micro}s pulse of electrons to 20 MeV. After acceleration, the 2-{micro}s pulse will be chopped into a train of four 50-ns pulses with variable temporal spacing by rapidly deflecting the beam between a beam stop and the final transport section. The short beam pulses will be focused onto an x-ray converter target generating four radiographic pulses within the 2-{micro}s window. Beam instability due to interaction with the accelerator cells can very adversely effect the beam brightness and radiographic pulse quality. This paper describes the various issues considered in the design of the accelerator cell with emphasis on transverse impedance and minimizing beam instabilities.

The PHENIX [Photon Electron New Heavy Ion Experiment] Detector is one of two large detectors presently under construction for RHIC (Relativistic Heavy Ion Collider) located at Brookhaven National Laboratory. Its primary goal is to detect a new phase of matter; the quark-gluon plasma. In order to achieve this objective, the PHENIX Detector utilizes a complex magnet subsystem which is comprised of two large magnets identified as the Central Magnet (CM) and the Muon Magnet (MM). Muon Identifier steel is also included as part of this package. The entire magnet subsystem stands over 10 meters tall and weighs in excess of 1900 tons (see Fig. 1). Magnet size alone provided many technical challenges throughout the design and fabrication of the project. In addition, interaction with foreign collaborators provided the authors with new areas to address and problems to solve. Russian collaborators would fabricate a large fraction of the steel required and Japanese collaborators would supply the first coil. This paper will describe the overall design of the PHENIX magnet subsystem and discuss its present fabrication status.

A model-based approach is developed to solve an adaptive ocean acoustic signal processing problem. Here we investigate the design of model-based identifier (MBID) for a normal-mode model developed from a shallow water ocean experiment and then apply it to a set of experimental data demonstrating the feasibility of this approach. In this problem we show how the processor can be structured to estimate the horizontal wave numbers directly from measured pressure sound speed thereby eliminating the need for synthetic aperture processing or a propagation model solution. Ocean acoustic signal processing has made great strides over the past decade necessitated by the development of quieter submarines and the recent proliferation of diesel powered vessels.

Sputtered thin film and multilayer x-ray mirrors are made routinely at the Advanced Photon Source (APS) for the APS users. Precise film growth control and characterization are very critical in fabricating high-quality x-ray mirrors. Film thickness calibrations are carried out using in situ and ex situ spectroscopic ellipsometry, interferometry, and x-ray scattering. To better understand the growth and optical properties of different thin film systems, we have carried out a systematic study of sputtered thin films of Au, Rh, Pg Pd, Cu, and Cr, using in situ ellipsometry. Multiple data sets were obtained in situ for each film material with incremental thicknesses and were analyzed with their correlation in mind. We found that in situ spectroscopic ellipsometry as a surface-sensitive tool can also be used to probe the growth and morphology of the thin film system. This application of in situ spectroscopic ellipsometry for metal thin film systems will be discussed.

When atomic photoionization is treated beyond the dipole approximation, photoelectron angular distributions are asymmetric forward and backward with respect to the direction of the photon beam. We have measured forward-backward asymmetries of Ar 1s and Kr 1s and 2s photoelectrons using 2-19 keV x-rays. The measured asymmetries compare well with calculations which include interference between electric-dipole and electric-quadrupole amplitudes within the nonrelativistic, independent-particle approximations.

Silicon Vertex tracks are of fundamental importance for reconstructing B meson decays at a hadron collider. The upgraded CDF detector will deploy an online Silicon Vertex Tracker in the level 2 trigger. We have studied how this new device exploits the Tevatron large B meson production to select hadronic B decays fundamental for measuring CP violation and B{sub s} mixing.

Grain growth experiments and simulations exhibit self-similar grain size distributions quite different from that derived via a mean field approach by Hillert [ 1]. To test whether this discrepancy is due to insufficient anneal times, two different two-dimensional grain structures with realistic topologies and Hillert grain size distributions are generated and subjected to grain growth via the Monte Carlo Potts Model (MCPM). In both cases, the observed self-similar grain size distributions deviate from the initial Hillert form and conform instead to that observed in MCPM grain growth simulations that start from a random microstructure. This suggests that the Hillert grain size distribution is not an attractor.