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This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a driver for the High-Flux Breeder Reactor (HFBR) at Brookhaven National Laboratory (BNL). The Linac operates in Continuous Wave (CW) mode to produce an average 10 MW of beam power. The Linac beam energy is 1.0 GeV. The average proton beam intensity in exit is 10 mA.

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An International Workshop on Metrology for X-ray and Neutron Optics has been held March 16-17, 2000, at the Advanced Photon Source, Argonne National Laboratory, near Chicago, Illinois (USA). The workshop gathered engineers and scientists from both the U.S. and around the world to evaluate metrology instrumentation and methods used to characterize surface figure and finish for long grazing incidence optics used in beamlines at synchrotrons radiation sources. This two-day workshop was motivated by the rapid evolution in the performance of x-ray and neutron sources along with requirements in optics figure and finish. More specifically, the performance of future light sources, such as free-electron laser (FEL)-based x-ray sources, is being pushed to new limits in term of both brilliance and coherence. As a consequence, tolerances on surface figure and finish of the next generation of optics are expected to become tighter. The timing of the workshop provided an excellent opportunity to study the problem, evaluate the state of the art in metrology instrumentation, and stimulate innovation on future metrology instruments and techniques to be used to characterize these optics. This paper focuses on FEL optics and metrology needs. (A more comprehensive summary of the workshop can be found elsewhere.) The performance …

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For a particle beam propagating in an alternating gradient focusing system, envelope equations are often employed to describe the evolution of the beam radii in the two directions transverse to the direction of propagation, and aligned with the principle axes of the alternating gradient system. When the beams have zero net angular momentum and when the alternating gradient focusing is approximated by a continuous focusing system, there are two normal modes to the envelope equations: the 'breathing' mode and a 'quadrupole' mode. In the former, the two radii oscillate in phase, and in the latter the radii oscillate 180 degrees out of phase. In this paper, we extend the analysis to include beams that have a finite angular momentum. We perturb the moment equations of ref. [1], wherein it was assumed that space charge is a distributed in a uniform density ellipse. Two additional modes are obtained. The breathing mode remains, but the quadrupole mode is split into two modes, and a new low frequency mode appears. We calculate the frequencies and eigenmodes of these four modes as a function of tune depression and a dimensionless net angular momentum. These modes can be excited by rotational errors of the quadrupoles …

The authors examine pair mass dependence near threshold as a means to measure the spin of the top quark in hadron collisions, and they discuss the possibility that a top quark signal could be hidden among the top events.

Making use of the measurement of the $B\to K^*\gamma$ branching ratio together with the relations following from the limit of high recoil energy, we obtain stringent constraints on the values of the form-factors entering in heavy-to-light $B\to V\ell\ell'$ processes such as $B\to K^*\ell^+\ell^-$, $B\to K^*\nu \bar\nu$ and $B\to \rho\ell\nu$ decays. We show that the symmetry predictions, when combined with the experimental information on radiative decays, specify a severely restricted set of values for the vector and axial-vector form-factors evaluated at zero momentum transfer, $q^2=0$. These constraints can be used to test model calculations and to improve our understanding of the $q^2$-dependence of semileptonic form-factors. We stress that the constraints remain stringent even when corrections are taken into account.

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Events with signatures involving large missing transverse energy (E{sub T}) are among the quintessential search modes for R-parity conserving supersymmetry. CDF has conducted two recent analyses for supersymmetry which use E{sub T} and jets. The E{sub T} and monojet signature is employed to determine process independent limits for the production of new physics beyond the Standard Model and then applied to models of spontaneous breaking of supersymmetry to determine limits on the supersymmetry breaking parameter and the gravitino mass. Direct searches for scalar top and scalar bottom quarks within the framework of supersymmetric models are performed using a signature of E{sub T} and two heavy flavor jets. Since the data is found to be consistent with Standard Model expectations, limits are determined in the mass planes m({tilde {chi}}{sub 1}{sup 0})-m({tilde t}{sub 1}) and m({tilde {chi}}{sub 1}){sup 0}-m({tilde b}{sub 1}).

A mobile 480-V, 2-MVA UPS System utilizing battery energy storage was installed at S and C Electric Company's Polymer Products Fabrication Building in Chicago, Illinois in May 1999 to provide uninterrupted power to the building for up to 15 seconds in the event of a voltage sag or momentary interruption in the local utility supply. Similar units can be applied at medium voltage through the application of a step-up transformer to provide momentary power disturbance ride through of up to 30 seconds for loads up to 15 MVA at system voltages ranging from 4.16 kV to 34.5 kV. A power quality evaluation of the installation was performed over a six-month period from July 1999 to early January 2000. This paper describes the details and results of this power quality evaluation, which involved two phases. Phase I involved the collection and review of power disturbance data and the effects on process equipment, while Phase II involved power quality monitoring of utility source and building load voltages and currents over a period of six months. Review of power disturbance data and equipment power-disturbance ride-through characteristics during Phase I of the project indicated that the polymer fabrication process in the building is affected …

This paper illustrates the application of evolutionary algorithms (EAs) to the problem of oblique decision tree induction. The objectives are to demonstrate that EAs can find classifiers whose accuracy is competitive with other oblique tree construction methods, and that this can be accomplished in a shorter time. Experiments were performed with a (1+1) evolutionary strategy and a simple genetic algorithm on public domain and artificial data sets. The empirical results suggest that the EAs quickly find Competitive classifiers, and that EAs scale up better than traditional methods to the dimensionality of the domain and the number of training instances.

The DOIM (Dense Optical-electrical Interface Modules) is a custom-designed optical data transmission module employed in the upgrade of Silicon Vertex Detector of CDF experiment at Fermilab. Each DOIM module consists of a transmitter (TX) converting electrical differential input signals to optical outputs, a middle segment of jacketed fiber ribbon cable, and a receiver (RX) which senses the light inputs and converts them back to electrical signals. The targeted operational frequency is 53 MHz, and higher rate is achievable. This article outlines the design goals, implementation methods, production test results, and radiation hardness tests of these modules.

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The authors report on the status of the new short bunch, high intensity electron gun at the Argonne Wakefield Accelerator. The 1-1/2 cell L-band photocathode RF gun is expected to produce 10--100 nC bunches with 2--5 ps rms pulse length and normalized emittance less than 100 mm mrad. The beam energy at the exit of the gun cavity will be in the range 7.5--10 MeV. A standing-wave linac structure operating at the same frequency (1.3 GHz) will increase the beam energy to about 15 MeV. This beam will be used in wakefield acceleration experiments with dielectric loaded structures. These travelling-wave dielectric loaded structures, operating at 7.8 and 15.6 GHz, will be excited by the propagation of single bunches or by trains of up to 32 electron bunches.

Double-diffusive finger convection is a hydrodynamic instability that can occur when two components with different diffusivities are oppositely stratified with respect to the fluid density gradient as a critical condition is exceeded. Laboratory experiments were designed using sodium chloride and sucrose solutions in a Hele-Shaw cell. A high resolution, full field, light transmission technique was used to study the development of the instability. The initial buoyancy ratio (R{sub p}), which is a ratio of fluid density contributions by the two solutes, was varied systematically in the experiments so that the range of parameter space spanned conditions that were nearly stable (R{sub p} = 2.8) to those that were moderately unstable (R{sub p} = 1.4). In systems of low R{sub p}, fingers develop within several minutes, merge with adjacent fingers, form conduits, and stall before newer-generated fingers travel through the conduits and continue the process. Solute fluxes in low R{sub p} systems quickly reach steady state and are on the order of 10{sup {minus}6} m{sup 2} sec{sup {minus}1}. In the higher R{sub p} experiments, fingers are slower to evolve and do not interact as dynamically as in the lower R{sub p} systems. Our experiment with initial R{sub p} = 2.8 exhibited …

In this investigation, YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) films were fabricated via a metal acetate, trifluoroacetic acid based sol-gel route, and spin-coat deposited on (100) LaAlO{sub 3} with a focus on maximizing J{sub c}, while minimizing processing time. We demonstrate that the use of a low pO{sub 2} atmosphere during the pyrolysis stage can lead to at least a tetiold reduction in pyrolysis time, compared to a 1 atm. O{sub 2} ambient. High-quality YBCO films on LaAlO{sub 3}, with J{sub c} values up to 3 MA/cm{sup 2} at 77 K, can be routinely crystallized from these rapidly pyrolyzed films.

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The goal of this work was to determine the effects on plutonium isotopic analysis of having plutonium inside of a 0.25 inch thick stainless steel can. To do this, they analyzed plutonium samples with a U-Pu InSpector (which uses a high-resolution gamma-ray detector and the analysis code MGA (Multi Group Analysis)), to determine both the 240-Pu/239-Pu ratio and the years since the plutonium was separated from americium. They analyzed a 1.6 kg plutonium sample that was placed inside of a 0.25 inch can at varying distances (0-2 meters) and count times (10 seconds-30 minutes). In separate experiments, they analyzed 0.4g plutonium sources with stainless-steel thickness' ranging from 0.125 to 1.0 inch. This report will show three effects of having plutonium in a stainless steel can: (1) 240-Pu/240-Pu can be quickly and accurately determined for a 1.6 kg plutonium sample inside of a 0.25 inch thick stainless-steel can, as this thickness of stainless steel acts as a perfect filter to reduce the intense 59 keV gamma peak from 241-Am. (2) The accuracy of determining the plutonium-americium separation date is not effected by 0.25 inch of stainless steel. (3) Both 240-Pu/239-Pu and the americium separation date can be accurately determined for stainless-steel …

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The authors are particularly interested in the work of adhesion measurements as a means to facilitate the understanding of the adhesive failure mechanisms for systems containing encapsulated and bonded components. Of the several issues under investigation, one is the effect of organic contamination on the adhesive strength for several types of polymer/metal interface combinations. The specific question that the authors are trying to address is at what level of contamination does adhesive strength decrease. The use of contact mechanics, the JKR method, is a good approach for studying this question. Another approach being studied is the use of interracial fracture mechanics. The model contaminant is hexadecane--non-polar, medium molecular weight hydrocarbon fluid. They choose hexadecane because it replicates typical machining fluids, is nonreactive with Al surfaces, and should not dissolve readily into the adhesive systems of interest. The application of a uniform, controllable and reproducible hexadecane layer on Al surfaces has proven to be difficult. A primary concern is whether studies of model systems can be extended to systems of technological interest. The JKR theory is a continuum mechanics model of contact between two solid spheres that was developed by Johnson, Kendall and Roberts. The JKR theory is an extension of …

A scalable, distributed modeling and simulation framework has been developed at Argonne National Laboratory to study Intelligent Transportation Systems. The framework can run on a single-processor workstation, or run distributed on a multiprocessor computer or network of workstations. The framework is modular and supports plug-in models, hardware, and live data sources. The initial set of models currently includes road network and traffic flow, probe and smart vehicles, traffic management centers, communications between vehicles and centers, in-vehicle navigation systems, roadway traffic advisories. The modeling and simulation capability has been used to examine proposed ITS concepts. Results are presented from modeling scenarios from the Advanced Driver and Vehicle Advisory Navigation Concept (ADVANCE) experimental program to demonstrate how the framework can be used to evaluate the benefits of ITS and to plan future ITS operational tests and deployment initiatives.

Because of their strong internal bonding, S-decorated Cu trimers are a likely agent of S-enhanced Cu transport between islands on Cu(111). According to ab-initio calculations, excellent healing of dangling Cu valence results in an ad-Cu{sub 3}S{sub 3} formation energy of only {approximately}0.28 eV, compared to 0.79 eV for a self-adsorbed Cu atom, and a diffusion barrier {le}0.35 eV.