Data from e/sup +/e/sup -/ annihilations at 29 GeV have been used to measure the production and fragmentation of eta mesons. The signal is observed in the eta ..-->.. ..gamma gamma.. decay channel. The fragmentation function for p/sub eta/ > 1.5 GeV/c agrees well with the shapes predicted by both the Lund and Webber models. However, the mean multiplicity is measured to be < n/sub eta/ > = 0.37 +- 0.08 eta mesons per hadronic annihilation event, which is significantly lower than the values predicted by either model. 6 refs., 2 figs., 1 tab.

Charged particle multiplicity distributions from e{sup +}e{sup {minus}} annihilations at 29 GeV have been analyzed in selected rapidity and azimuthal angle intervals. The data were taken with the High Resolution Spectrometer at PEP. The factorial moments of the multiplicity distributions increase as the rapidity interval is decreased, the so-called intermittency phenomenon. These direct measurements of the moments agree with values derived from negative binomial fits to our multiplicity distributions in various central rapidity windows. The factorial moments are also given for the distribution in azimuthal angle around the beam direction and for the two-dimensional distribution in rapidity and azimuthal angle around the jet directions.

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Abstract: We present the results of a search for anomalous resonant production of tau lepton pairs with large invariant mass, the first such search using the CDF II Detector in Run II of the Tevatron p{bar p} collider. Such anomalous production could arise from various new physics processes. In a data sample corresponding to 195 pb{sup -1} of integrated luminosity we predict 2.8 {+-} 0.5 events from Standard Model background processes and observe 4. We use this result to set limits on the production of heavy scalar and vector particles decaying to tau lepton pairs.

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The present state of understanding of localized corrosion of passive metals is based primarily upon behavior under fully immersed solutions. There has been limited analysis of localized corrosion in moist layers of dust, particulate and deposits. This work as part of a multi-university Corrosion Cooperative of the DOE-OCRWM Science and Technology Program established to enhance the understanding of corrosion processes and materials performance. The objective of this project is to develop models to simulate localized corrosion. The present analysis focuses specifically on the cathodic region near a corrosion crevice with the objective of characterizing the effects of the critical process parameters on the required current to sustain the crevice corrosion. Previous related analytical and numerical studies have focused on galvanic corrosion where the rates of the anodic and cathodic processes are comparable, analyzing mostly the effects of the electrode kinetics and the thickness of the electrolyte layer. A recent study considers the cathodic region for crevice corrosion. The work here determines two and three dimensional current and potential distributions over the cathode. The analyzed cathodic oxygen reduction region adjacent to the crevice is depicted in Fig. 1. This region is modeled for the presence of extremely thin (G{sub r} = …

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In this report, a method for solving this problem by treating the reaction region as a place of discontinuities in the appropriate variables, which include, for example, fluxes of heat and mass was proposed. Using a rigorous perturbation approach, similar to that used in the propagation of flames and smoldering combustion, appropriate jump conditions that relate the change in these variables across the front was derived. These conditions account for the kinetics of the reaction between the oxidant and the fuel, the changes in the morphology of the pore space and the heat and mass transfer in the reaction zone. The modeling of the problem reduces to the modeling of the dynamics of a combustion front, on the regions of either side of which transport of momentum (fluids), heat and mass, but not chemical reactions, must be considered. Properties of the two regions are coupled using the derived jump conditions. This methodology allows one to explicitly incorporate permeability heterogeneity effects in the process description, without the undue complexity of the coupled chemical reactions.

This report discusses research at the Hanford production reactors on reactor materials and reactor technology.

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The objective of this study is to develop and field test a new, integrated Hybrid Hydrologic-Geophysical Inverse Technique (HHGIT) for characterization of the vadose zone at contaminated sites. This new approach to site characterization and monitoring can provide detailed maps of hydrogeological heterogeneity and the extent of contamination by combining information from 3D electric resistivity tomography (ERT) and/or 2D cross borehole ground penetrating radar (XBGPR) surveys, statistical information about heterogeneity and hydrologic processes, and sparse hydrologic data. Because the electrical conductivity and dielectric constant of the vadose zone (from the ERT and XBGPR measurements, respectively) can be correlated to the fluid saturation and/or contaminant concentration, the hydrologic and geophysical measurements are related.

The feasibility of using nanosensors to measure temperature distribution and predict thermal breakthrough in geothermal reservoirs is addressed in this report. Four candidate sensors were identified: melting tin-bismuth alloy nanoparticles, silica nanoparticles with covalently-attached dye, hollow silica nanoparticles with encapsulated dye and impermeable melting shells, and dye-polymer composite time-temperature indicators. Four main challenges associated with the successful implementation of temperature nanosensors were identified: nanoparticle mobility in porous and fractured media, the collection and detection of nanoparticles at the production well, engineering temperature sensing mechanisms that are both detectable and irreversible, and inferring the spatial geolocation of temperature measurements in order to map temperature distribution. Initial experiments were carried out to investigate each of these challenges. It was demonstrated in a slim-tube injection experiment that it is possible to transport silica nanoparticles over large distances through porous media. The feasibility of magnetic collection of nanoparticles from produced fluid was evaluated experimentally, and it was estimated that 3% of the injected nanoparticles were recovered in a prototype magnetic collection device. An analysis technique was tailored to nanosensors with a dye-release mechanism to estimate temperature measurement geolocation by analyzing the return curve of the released dye. This technique was used in a hypothetical …

JANUS, a two-sided, interactive wargame simulation code, was used to explore how using each of several different yield options in a nuclear artillery shell might affect a tactical battlefield simulation. In a general sense, the results or outcomes of these simulations support the results or outcomes of previous studies. In these simulations the Red player knew of the anticipated nuclear capability of the Blue player. Neither side experienced a decisive win over the other, and both continued fighting and experienced losses that, under most historical circumstances, would have been termed unacceptable - that is, something else would have happened (the attack would have been called off). During play, each side had only fragmentary knowledge of the remaining resources on the other side - thus each side desired to continue fighting on the basis of known information. We found that the anticipated use of nuclear weapons by either side affects the character of a game significantly and that, if the employment of nuclear weapons is to have a decided effect on the progress and outcome of a battle, each side will have to have an adequate number of nuclear weapons. In almost all the simulations we ran using JANUS, enhanced radiation …

Reactivity and fuel burnup studies were performed for a 255 Mw(e) sodium- graphite reactor of the advanced calandria core type. This reactor is briefly described. Initial criticality calculations and flux distributions were obtained, using two-group theory for enrichments between 2.0 at.% U/sup 325/ and 4.0 at.% U235. A four-group burnup study was performed for enrichments between 2.5 at.% Uisup nd 3.25 at.% U/sup 235/. Core lifetime, changes in isotopic fuel composition, variations in radial power distribution, and fuel cross sec tions are presented. Reactivity during core lifetime was assumed to be controlled by the presence of a homogeneous poison which simulated the effects of control rcds. The results presentad are useful in determining initial enrichment selection in fuel programming and fuel cost studies. (auth)

Nitrosomonas europaea is an aerobic lithoautotrophic bacterium that uses ammonia (NH3) as its energy source. As a nitrifier, it is an important participant in the nitrogen cycle, which can also influence the carbon cycle. The focus of this work was to explore the genetic structure and mechanisms underlying the lithoautotrophic growth style of N. europaea. Whole genome gene expression. The gene expression profile of cells in exponential growth and during starvation was analyzed using microarrays. During growth, 98% of the genes increased in expression at least two fold compared to starvation conditions. In growing cells, approximately 30% of the genes were expressed eight fold higher, Approximately 10% were expressed more than 15 fold higher. Approximately 3% (91 genes) were expressed to more than 20 fold of their levels in starved cells. Carbon fixation gene expression. N. europaea fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). This study showed that transcription of cbb genes was up-regulated when the carbon source was limited, while amo, hao and other energy harvesting related genes were down-regulated. Iron related gene expression. Because N. europaea has a relatively high content of hemes, sufficient Fe must be available in the …

Presentation given by Dan Arvizu at the Center for Strategic and International Studies (CSIS) Symposium on Future Fuels on June 15, 2006

Presented at the Center for Strategic and International Studies' Energy Program and Global Strategy Institute Series on Alternative Fuels on June 15, 2006 by Dr. Dan Arvizu.

We analyze M-theory compactified on K3 x K3 with fluxes preserving half the supersymmetry and its F-theory limit, which is dual to an orientifold of the type IIB string on K3 x (T{sup 2}/Z{sub 2}). The geometry of attractive K3 surfaces plays a significant role in the analysis. We prove that the number of choices for the K3 surfaces is finite and we show how they can be completely classified. We list the possibilities in one case. We then study the instanton effects and see that they will generically fix all of the moduli. We also discuss situations where the instanton effects might not fix all the moduli.

We report on a study of inclusive B{sup -} and {bar B}{sup 0} meson decays to D{sup 0}X, {bar D}{sup 0}X, D{sup +}X, D{sup -}X, D{sub s}{sup +}X, D{sub s}{sup -}X, {Lambda}{sub c}{sup +}X, {bar {Lambda}}{sub c}{sup -}X, based on a sample of 231 million B{bar B} events recorded with the BABAR detector at the {Upsilon}(4S) resonance. Events are selected by completely reconstructing one B and searching for a reconstructed charm particle in the rest of the event. From the measured branching fractions of these decays, we infer the number of charm and anti-charm particles per {bar B} decay, separately for charged and neutral parents. We derive the total charm yield per B{sup -} decay, n{sub c}{sup -} = 1.202 {+-} 0.023 {+-} 0.040{sub -0.029}{sup +0.035}, and per {bar B}{sup 0} decay, n = 1.193 {+-} 0.030 {+-} 0.034{sub -0.035}{sup +0.044} where the first uncertainty is statistical, the second is systematic, and the third reflects the charm branching-fraction uncertainties. We also present the charm momentum distributions measured in the {bar B} rest frame.

The purpose of this test is to provide a set of experimental data to test a compute code frequently used in nuclear safety analyses and to explore certain experimental techniques which may prove extremely valuable in the future. In addition, some basic physics parameters which will be measured may be used in an assessment of the feasibility of using a deactivated Hanford reactor for space-dependent transient tests.

The oxidation resistance of protective capping layers for extreme ultraviolet lithography (EUVL) multilayers depends on their microstructure. Differently prepared Ru-capping layers, deposited on Mo/Si EUVL multilayers, were investigated to establish their baseline structural, optical, and surface properties in as-deposited state. The same capping layer structures were then tested for their thermal stability and oxidation resistance. The best performing Ru-capping layer structure was analyzed in detail with transmission electron microscopy (TEM). As compared to other Ru capping layers preparations studied here it is the only one that shows grains with preferential orientation. This information is essential for modeling and performance optimization of EUVL multilayers.

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Recent developments in high reliability components for linear induction accelerators (LIA) make possible the use of LIAs as large-scale, economical sources of radio-frequency (rf) power for many applications. One particularly attractive example of interest to high energy physicists is a ''two-beam accelerator'' version of a linear e/sup +/-e/sup -/ collider at TeV energies in which the LIA is configured as a monolithic relativistic klystron operating at 10 to 12 GHz. Another example of keen interest to the fusion community is the use of the LIA to drive a free-electron laser operating at 200 to 500 GHz for use in heating fusion plasma via electron resonance cyclotron heating. This paper briefly describes several potential uses of LIA radiation sources. It discusses the physical basis for scaling our present experience with LIAs to the operating characteristics applicable to large-scale sources of rf power and synchrotron radiation. 14 refs., 6 figs., 1 tab.

This report summarizes results obtained on the thermodynamic and kinetic properties of zeolites. DOE funding supported the development of techniques of material preparation as well as experimental strategies and methods for measuring solubilities, hydration states, and rates of zeolite dissolution, precipitation, and nucleation. The hydrothermal experiments provided temperature-dependent solubility products, hydration states, and a set of standard free energies of formation for end-member Na-, K-, and Ca-clinoptilolite, mordenite, and analcime. Flow-through experimental methods were used to measure the rates of Na-clinoptilolite and analcime dissolution and precipitation as a function of reaction affinity to 250C. Finally, the experimental system was modified so that the clinoptilolite-to-analcime transformation was monitored, and its rates and mechanisms were evaluated.