In this paper we investigate the microstructural accommodation of nonstoichiometry in (Ba{sub x}Sr{sub 1{minus}x}Ti{sub 1+y}O{sub 3+z}) thin films grown by chemical vapor deposition. Films with three different (Ba+Sr)/Ti ratios of 49/51 (y=0.04 in the notation of the formula above), of 48/52 (y=0.08) and of 46.5/53.5 (y=O.15), were studied. High-resolution electron microscopy is used to study the microstructure of the BST films. High-spatial resolution electron energy-loss spectroscopy (EELS) is used to reveal changes in chemistry and local atomic environment both at grain boundaries and within grains as a function of titanium excess. We find an amorphous phase at the grain boundaries and grain boundary segregation of excess titanium in the samples with y=0.15. In addition, EELS is also used to show that excess titanium is being partially accommodated in the grain interior. Implications for the film electrical and dielectric properties are outlined.

Infrared thermal imaging has become increasingly popular as a nondestructive evaluation method for characterizing materials and detecting defects. One technique, which was utilized in this study, is front-flash thermal imaging. We have developed a thermal imaging system that uses this technique to characterize advanced material systems, including continuous fiber ceramic composite (CFCC) components. In a front-flash test, pulsed heat energy is applied to the surface of a sample, and decay of the surface temperature is then measured by the thermal imaging system. CFCC samples with drilled flat-bottom holes at the back surface (to serve as ''flaws'') were examined. The surface-temperature/time relationship was analyzed to determine the depths of the flaws from the front surface of the CFCC material. Experimental results on carbon/carbon and CFCC samples are presented and discussed.

We have seen that many different types of intermolecular interactions in organic conducting cation radical salts. Hydrogen bonding between the donor molecules and the anions is weak but not negligible. The ionic Madelung energy is insufficient to completely intersperse anions and cations, thus the layers favored by the van der Waals interactions remain intact. The search for new conducting and superconducting salts has been mainly by trial-and-error methods, even though simple substitutions have been employed in order to obtain isostructural analogs of successful (e.g., superconducting) salts. However, even seemingly minor substitutions sometimes destroy the packing type, and different crystal structures result. Simulations with the aim at predicting crystal structures have not succeeded, mainly because the different interaction types are of comparable energy, and the delocalized and partial charges render the calculations of the ionic terms extremely unreliable. Clearly, the development of suitable crystal modeling techniques with predictive capabilities is one of the great needs of the field.

One of the crucial predictions of supersymmetric models that reduce to the Minimal Supersymmetric Standard Model (MSSM) at the weak scale is that the lightest Higgs scalar should have mass m{sub h} {approx_lt} 125-130 GeV[1]. Recent results on the reach of Fermilab Tevatron upgrades for Standard Model (SM) Higgs bosons show that masses of order 120-180 GeV may be probed [2, 3, 4, 5], depending on integrated luminosity, detector performance and signal and background modeling. Thus, the discovery of a Higgs boson (or a new limit of around 120-130 GeV on its mass) will severely constrain supersymmetric models as well. In this report, we update previous calculations made by our group [6] pertaining to the reach of Fermilab Tevatron upgrades for Higgs bosons in supersymmetric models. We present reach results for SUSY Higgs bosons within the MSSM, the minimal Supergravity model (mSUGRA) and in the minimal Gauge Mediated SUSY Breaking model (mGMSB). In this update, 95% CL exclusion contours and 5{sigma} discovery contours are presented for integrated luminosity values of 2, 5 and 20 fb{sup {minus}1}.

A quantitative model is under development to assess the safety and efficiency of commercial aircraft operations under the Free Flight Program proposed for air traffic control for the US National Airspace System. The major objective of the Free Flight Program is to accommodate the dramatic growth anticipated in air traffic in the US. However, the potential impacts upon aircraft safety from implementing the Program have not been fully explored and evaluated. The model is directed at assessing aircraft operations at high altitude over the continental US airspace since this action is the initial step for Free Flight. Sequential steps with analysis, assessment, evaluation, and iteration will be required to satisfactorily accomplish the complete transition of US commercial aircraft traffic operations.

The National Ignition Facility (NIF) is a 1.8 MJ (at 351 nm), 192 beam laser facility being built at the Lawrence Livermore National Laboratory (LLNL) to achieve inertial fusion ignition in the laboratory. The NIF Project is being designed and built by a team from LLNL, Los Alamos National Laboratory, Sandia National Laboratory, and the University of Rochester. When completed in 2003, it will be a multipurpose facility that will be used for many applications in national security, energy, and the basic sciences. In addition to the National Security Mission, these applications include, for example, electric power generation, space propulsion, and study of basic astrophysical phenomena in the laboratory. Such applications receive benefit both through the state- of-the-art technology developments necessary to build NIF and through specific experiments that will be performed on NIF.

The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively forged projectiles. LX- 19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOW-2, include the Apache helicopter. Loads associated with vibrations and expansion from thermal excursions in field operations may, even at low levels over long time periods, cause flaws, already present in the PBX to grow. Flaws near the explosive/liner interface of a shaped charge can reduce performance. Small flaws in explosives are one mechanism (the hot spot mechanism) proposed for initiation and growth to detonation of PBXs like LX-14, PBXN 5, LX-04 and LX-17 among others. Unlike cast-cured explosives and propellants, PBXs cannot usually be compression molded to full density. Generally, the amount of explosive ignited by a shock wave is approximately equal to the original void volume. Whether or not these flaws or cracks grow during field operations to an extent sufficient to adversely affect the shaped charge performance or increase the vulnerability of the PBX is the ultimate question this effort …

The porosities of three mesoporous silica materials were characterized with {sup 129}Xe NMR spectroscopy. The materials were synthesized by a sol-gel process with r = 0, 25, and 70% methanol by weight in an aqueous cetyltrimethylammonium bromide solution. Temperature dependent chemical shifts and spin lattice relaxation times reveal that xenon does not penetrate the pores of the largely disordered (r= 70%) silica. For both r = 0 and 25%, temperature dependent resonances corresponding to physisorbed xenon were observed. An additional resonance for the r = 25% sample was attributed to xenon between the disordered cylindrical pores. 2D NMR exchange experiments corroborate the spin lattice relaxation data which show that xenon is in rapid exchange between the adsorbed and the gas phase.

Progress towards the development of such algorithms as been reported for waveguide analysis'-3and vertical-cavity laser simulation. In all these cases, the higher accuracy order was obtained for a single spatial dimension. More recently, this concept was extended to differencing of the Helmholtz Equation on a 2-D grid, with uniform regions treated to 4th order and dielectric interfaces to 3'd order5. No attempt was made to treat corners properly. In this talk I will describe the extension of this concept to allow differencing of the Helmholtz Equation on a 2-D grid to 6* order in uniform regions and 5* order at dielectric interfaces. In addition, the first known derivation of a finite difference equation for a dielectric comer that allows correct satisfaction of all boundary conditions will be presented. This equation is only accurate to first order, but as will be shown, results in simulations that are third-order-accurate. In contrast to a previous approach3 that utilized a generalized Douglas scheme to increase the accuracy order of the difference second derivative, the present method invokes the Helmholtz Equation itself to convert derivatives of high order in a single direction into mixed

Using an automated magnet measurement system employing a variety of current excitation ramps, extensive studies of the hysteretic behavior of magnet strength have been carried out. An analytic description which is accurate at better than 0.1% has been achieved. Prescriptions for setting field strength using these formulas will be adequate for multi-energy operation of the Fermilab Main Injector, for deceleration in the Main Injector and Accumulator and for multi-energy operation of various beamline magnets. An overview of this work is provided. Important regularities of the magnet behavior are identified.

The Main Injector is a new rapid cycling accelerator at Fermilab which is a source of protons to be used in antiproton production to enhance the luminosity of the Tevatron Collider and to provide extracted beams for use in a range of fixed target experiments. We discuss the current status of the accelerator and the physics which it enables. The physics ranges broadly over the standard model and beyond, from the search for neutrino mass to collider physics at the highest energy available today.

NIST-built 10 T{Omega} and commercial 1 T{Omega} standard resistors were hand carried between NIST and Sandia for a high resistance comparison. The comparison tested the ruggedness of the new NIST-built standard resistors, provided a check of the scaling between the two laboratories, supported measurements to reestablish NIST calibration services at 10 T{Omega} and 100 T{Omega}, and demonstrated the possibility of establishing a NIST high resistance measurement assurance program (MAP). The comparison has demonstrated agreement on the order of 0.07% which is within the expanded uncertainties (coverage factor = 2) of NIST and Sandia at 1 T{Omega} and 10 T{Omega}.

As a part of the Fermilab high field Nb{sub 3}Sn dipole development program, various issues of magnet technology are being investigated. In cable insulation development, S-2 fiber glass sleeve and a new ceramic insulation developed by Composite Technology Development Inc. (CTD) were studied as a possible candidates. For each type of insulation, Nb{sub 3}Sn ten-stack samples were reacted and then vacuum impregnated with epoxy. Measurements of modulus of elasticity and Poisson�s ratio under compression were made at room temperature and at 4.2 K. For comparison, an epoxy impregnated NbTi composite was also tested.

The U. S. Environmental Protection Agency (EPA) issued revised Resource Conservation and Recovery Act (RCRA) Phase IV Land Disposal Restrictions (LDR's) on May 26 1998. The new regulation requires that any waste characteristically hazardous for the metals As, Ba, Cd, Cr, Pb, Hg, Se, and Ag will have to be treated to meet the LDR Universal Treatment Standards (UTS) for each metal prior to land disposal. Since EPA regulations continue to become more stringent, here-to-fore unpublished TCLP data generated during testing of simulated High Level Waste (HLW) glass, including the Evnironmental Assessment glass and K-3 melter refractory, will be reviewed. The refractory TCLP data compilation includes K-3 refractory in contact with DWPF simulated glass in a pilot scale melter and K-3 refractory in contact with actual mixed waste glass in a 5 ton a day GTS Duratek melter.

Phase separation is shown to have an adverse and unpredictable effect on durability of borosilicate nuclear waste glasses. The glass chemistry and thermal history of the waste glass during solidification in a canister can impact the kinetics of phase separation and thus, the long term durability of a the glass. Although waste glasses contain 15-20 components, many of the components are present in minor amounts. Greater than 95 percent of the glass chemistry is dominated by the seven major components, Na2O- K2O-Li2O-SiO2-Al2O3-B2O3-Fe2O3. Although the phase equilibria of this seven component system has never been studied, a compositionally dependent "Phase Separation Discriminator" was developed from a database of 88 High Level Waste (HLW) glasses shown experimentally to be homogeneous and 22 shown experimentally to be phase separated. This discriminator ensures that the HLW glasses produced in the Defense Waste Processing Facility (DWPF) are homogeneous and have predictable long term durability.

The dynamic aperture for version 5.1, with a 300{mu}r crossing angle at IP1 and IP5, of the Large Hadron Collider (LHC) lattice has been estimated using the tracking code TEVLAT. The dynamic aperture calculated here is due to the magnetic field errors in the high gradient quadrupoles (MQX) in the two low-{beta} interaction regions at IR1 and IR5. No errors were assigned to the magnets in the arc regions of the lattice, nor were beam-beam effects incorporated. The dynamic aperture is expressed in terms of the {sigma} of the beam corresponding to the beam emittance of 3.75mm mr. With only short term tracking, the combined effect of the multipoles and the crossing angle is to yield an average (over multipole coefficients generated with 100 different seeds) dynamic aperture of {approx} 11.7 {plus_minus} 1.2{sigma}.

Epitaxial, conductive-oxide buffer layers having bilayer configurations have been deposited on biaxially textured nickel substrates (RABiTS) by rf and dc-sputter techniques. The conductive bilayer structures comprise the layer sequences of SrRuO{sub 3}/LaNiO{sub 3}/Ni and SrRuO{sub 3}/Cu/Ni. Systematic property characterizations of the buffer layers showed excellent electrical and structural properties. High-quality epitaxial YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films grown by pulsed-laser deposition on these structures exhibited critical current densities (J{sub c}) as high as 1.3 x 10{sup 6} A/cm{sup 2} at 77 K in self-field.

Light-duty chassis dynamometer driving cycle tests were conducted on a Mercedes A170 diesel vehicle with various sulfur-level fuels and exhaust emission control systems. Triplicate runs of a modified light-duty federal test procedure (FTP), US06 cycle, and SCO3 cycle were conducted with each exhaust configuration and fuel. Ultra-low sulfur (3-ppm) diesel fuel was doped to 30- and 150-ppm sulfur so that all other fuel properties remained the same. The fuels used in these experiments met the specifications of the fuels from the DECSE (Diesel Emission Control Sulfur Effects) program. Although the Mercedes A170 vehicle is not available in the US, its emissions in the as tested condition fell within the U.S. Tier 1 full useful life standards with the OEM catalysts installed. Tests with the OEM catalysts removed showed that the OEM catalysts reduced PM emissions from the engine-out condition by 30-40% but had negligible effects on NOx emissions. Fuel sulfur level had very little effect on th e OEM catalyst performance. A prototype catalyzed diesel particulate filter (CDPF) mounted in an underfloor configuration reduced particulate matter emissions by more than 90% compared to the factory emissions control system. The results show that the CDPF did not promote any significant amounts …

A study of siting considerations for possible future accelerators at Fermilab is underway. Each candidate presents important challenges in environment, safety, and health (ES&H) that are reviewed generically in this paper. Some of these considerations are similar to those that have been encountered and solved during the construction and operation of other accelerator facilities. Others have not been encountered previously on the same scale. The novel issues will require particular attention coincident with project design efforts to assure their timely cost-effective resolution. It is concluded that with adequate planning, the issues can be addressed in a manner that merits the support of the Laboratory, the US Department of Energy (DOE), and the public.

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The transverse polarization observed in the inclusive production of {Lambda} hyperons in the high energy collisions of unpolarized hadrons is tackled by considering a new set of spin and {kappa}{perpendicular} dependent quark fragmentation functions. Simple phenomenological expressions for these new ''polarizing fragmentation functions'' are obtained by a fit of the data on {Lambda}'s and {bar {Lambda}}'s produced in p - N processes.

The photoionization spectrum of helium near the double-ionization threshold shows structure which indicated a transition towards quantum chaos.

We study the fragmentation of a transversely polarized quark into a non-collinear (k{perpendicular} {ne} 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative properties are described by spin and k{perpendicular} dependent fragmentation functions and are revealed in the observation of single spin asymmetries. Recent data on the production of pions in polarized semi-inclusive DIS and long known data on A polarization in unpolarized p-N processes are considered: these new fragmentation functions can describe the experimental results and the single spin effects in the quark fragmentation turn out to be surprisingly large.

Computational fluid-dynamics numerical models are developed for joule-heated slurry fed waste glass melters, such as the Defense Waste Processing Facility Melter. An important feature of the analyses is the simulation of the cold cap region with its thermally resistant foamy layer. Using a simplified model which describes the foam void fraction as a function of temperature, based on laboratory sample testing, characteristic features of the cold cap are simulated. Two- and three-dimensional models are presented.