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D0 papers on B-physics submitted to DPF '96: b-quark inclusive cross sections and b anti-b correlations using dimuons from the D0 experiment; Single muon production in the forward region at [radical]s=1. 8 TEV; Rapidity dependence of the inclusive J[psi] production in the forward region [radical]s=1. 8 TEV; A search for b [r arrow] X[mu][sup +][mu][sup [minus]] and B[sup 0] [r arrow] [mu][sup +][mu][sup [minus]] decays in p anti-p collisions at [radical]s=1. 8 TEV (open access)

D0 papers on B-physics submitted to DPF '96: b-quark inclusive cross sections and b anti-b correlations using dimuons from the D0 experiment; Single muon production in the forward region at [radical]s=1. 8 TEV; Rapidity dependence of the inclusive J[psi] production in the forward region [radical]s=1. 8 TEV; A search for b [r arrow] X[mu][sup +][mu][sup [minus]] and B[sup 0] [r arrow] [mu][sup +][mu][sup [minus]] decays in p anti-p collisions at [radical]s=1. 8 TEV

Paper 1: Using dimuons collected with the D0 detector during the 1993--1995 Tevatron collider run, the authors have measured the b-quark cross section and b[anti b] correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors. (Three other papers are included in this report.)
Date: November 1, 1996
Creator: Vititoe, D.L. (Arizona Univ., Tucson, AZ (United States). Dept. of Physics); Kozelov, Alexander; Jesik, Richard & Collaboration., D0
System: The UNT Digital Library
Design and Construction of the PEP-II Low Energy Ring (open access)

Design and Construction of the PEP-II Low Energy Ring

We describe the design and construction status of theLow-Energy Ring (LER) of the PEP-II project, a collaboration of SLAC,LBNL, and LLNL. In the past year we have optimized LER parameters andstarted component fabrication. By reusing the original wigglers, we wereable to simplify the design of the distributed wiggler photon dump, whichmust dissipate 260 kW of power. The number of RF stations (eachcomprising a klystron powering two 476-MHz cavities) was reduced from 4to 3. We have begun fabrication of the arc vacuum system based on anextruded Al antechamber configuration with discrete photon stops andTSPs. The design of the straight section vacuum components, to befabricated from stainless steel pipe, is also completed. Quadrupoles anddipoles are provided under a collaborative agreement with IHEP (Beijing);correctors and skew quadrupoles are built domestically and sextupoles arerefurbished from existing PEP magnets. LER commissioning will begin earlyin 1998.
Date: June 1, 1996
Creator: Hsieh, H.; Yourd, R. & Zisman, M. S.
System: The UNT Digital Library
Regional and National Estimates of the PotentialEnergy Use, Energy Cost, and CO{sub 2} Emissions Associated with Radon Mitigation by Sub-slab Depressurization (open access)

Regional and National Estimates of the PotentialEnergy Use, Energy Cost, and CO{sub 2} Emissions Associated with Radon Mitigation by Sub-slab Depressurization

Active sub-slab depressurization (SSD) systems are an effective means of reducing indoor radon concentrations in residential buildings. However, energy is required to operate the system fan and to heat or cool the resulting increased building ventilation. We present regional and national estimates of the energy requirements, operating expenses, and CO{sub 2} emissions associated with using SSD systems at saturation (i.e., in all U.S. homes with radon concentrations above the EPA remediation guideline and either basement or slab-on-grade construction). The primary source of uncertainty in these estimates is the impact of the SSD system on house ventilation rate. Overall, individual SSD system operating expenses are highest in the Northeast and Midwest at about $99 y{sup -1}, and lowest in the South and West at about $66 y{sup -1}. The fan consumes, on average, about 40% of the end-use energy used to operate the SSD system and accounts for about 60% of the annual expense. At saturation, regional impacts are largest in the Midwest because this area has a large number of mitigable houses and a relatively high heating load. We estimate that operating SSD systems in U.S. houses where it is both appropriate and possible (about 2.6 million houses), will annually …
Date: March 1, 1996
Creator: Riley, W. J.; Fisk, W. J. & Gadgil, A. J.
System: The UNT Digital Library
Wind-induced Ground-surface Pressures Around a Single-Family House (open access)

Wind-induced Ground-surface Pressures Around a Single-Family House

Wind induces a ground-surface pressure field around a building that can substantially affect the flow of soil gas and thereby the entry of radon and other soil-gas contaminants into the building. To quantify the effect of the wind-induced groundsurface pressure field on contaminant entry rates, the mean ground-surface pressure field was experimentally measured in a wind tunnel for several incidence angles of the wind, two atmospheric boundary layers, and two house geometries. The experimentally measured ground-surface pressure fields are compared with those predicted by a k-e turbulence model. Despite the fundamental limitations in applying a k-e model to a system with flow separation, predictions from the numerical simulations were good for the two wind incidence angles tested.
Date: February 1, 1996
Creator: Riley, W. J.; Gadgil, A. J. & Nazaroff, W. W.
System: The UNT Digital Library
Progress on PEP-II Magnet Power Conversion System? (open access)

Progress on PEP-II Magnet Power Conversion System?

The various power systems for supplying the PEP-II DCmagnets rely exclusively on switch mode conversion, utilizing a varietyof means depending on the requirements. All of the larger power supplies,ranging from 10 to 200 kW, are powered from DC sources utilizingrectified 480 V AC. Choppers can be used for the series connectedstrings, but for smaller groups and individual magnets, inverters drivinghigh-frequency transformers with secondary rectifiers comprise the bestapproach. All of the various systems use a "building block" approach ofmultiple standard-size units connected in series or parallel to mostcost-effectively deal with a great range of voltage and currentrequirements. Utilization of existing infrastructure from PEP-I has beena cost-effective determinant. Equipment is being purchased eitheroff-the-shelf, through performance specification, or by hardware purchasebased on design-through-prototype. The corrector magnet power system,utilizing inexpensive, off-the-shelf four-quadrant switching motorcontrollers, has already proven very reliable: 120 of the total of 900units have been running on the injection system for four months with nofailures.
Date: June 1, 1996
Creator: Bellomo, P.; Genova, L.; Jackson, T. & Shimer, D.
System: The UNT Digital Library
Non-destructive evaluation techniques for chemical weapons destruction (open access)

Non-destructive evaluation techniques for chemical weapons destruction

fThe safe and verifiable disposition, either by incineration or chemical neutralization of chemical warfare (CW) agents requires correct {ital a priori} identification of each munition or container to be processed. A variety of NDE techniques have been used or tested for the examination and characterization of munitions. In the U.S., three widely used techniques are X-ray radiography, acoustic resonance spectroscopy (ARS), and prompt gamma ray neutron activation analysis (PINS). The technical bases, instrumental implementations, and applications of the U.S. versions of these methods are briefly discussed. 10 refs., 2 figs., 1 tab.
Date: September 1, 1996
Creator: Hartwell, J. K. & Caffrey, A. J.
System: The UNT Digital Library
B-Quark Inclusive Cross Sections and B{Bar B} Correlations Using Dimuons From the D0 Experiment (open access)

B-Quark Inclusive Cross Sections and B{Bar B} Correlations Using Dimuons From the D0 Experiment

Using dimuons collected with the D{null} detector during the 1993- 1995 Tevatron collider run, we have measured the {ital b}-quark cross section and {ital b{anti b}} correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors.
Date: November 1, 1996
Creator: Vititoe, D. L.
System: The UNT Digital Library
Test Results for a High Field (13T) Nb3Sn Dipole (open access)

Test Results for a High Field (13T) Nb3Sn Dipole

A Nb{sub 3}Sn dipole magnet (D20) has been designed, constructed, and tested at LBNL. Previously, they had reported test results from a hybrid design dipole which contained a similar inner Nb{sub 3}Sn and outer NbTi winding. This paper presents the final assembly characteristics and parameters which will be compared with those of the original magnet design. The actual winding size was determined and a secondary calibration of the assembly pre-load was done by pressure sensitive film. The actual azimuthal and radial D20 pre-loading was accomplished by a very controllable novel stretched wire technique. D20 reached 12.8T(4.4K) and 13.5T(1.8K) the highest dipole magnetic fields obtained to date in the world.
Date: December 1, 1996
Creator: McInturff, A.D.; Benjegerdes, R.; Bish, P.; Caspi, S.; Chow, K.; Ell'Orco, D. et al.
System: The UNT Digital Library
Bayesian Prediction of Mean Indoor Radon Concentrations for Minnesota Counties (open access)

Bayesian Prediction of Mean Indoor Radon Concentrations for Minnesota Counties

Past efforts to identify areas with higher than average indoor radon concentrations by examining the statistical relationship between local mean concentrations and physical parameters such as the soil radium concentration have been hampered by the variation in local means caused by the small number of homes monitored in most areas. In this paper, indoor radon data from a survey in Minnesota are analyzed to minimize the effect of finite sample size within counties, to determine the true county-to-county variation of indoor radon concentrations in the state, and to find the extent to which this variation is explained by the variation in surficial radium concentration among counties. The analysis uses hierarchical modeling, in which some parameters of interest (such as county geometric mean (GM) radon concentrations) are assumed to be drawn from a single population, for which the distributional parameters are estimated from the data. Extensions of this technique, known as a random effects regression and mixed effects regression, are used to determine the relationship between predictive variables and indoor radon concentrations; the results are used to refine the predictions of each county's radon levels, resulting in a great decrease in uncertainty. The true county-to-county variation of GM radon levels is …
Date: February 1, 1996
Creator: Price, P. N.; Nero, A. V. & Gelman, A.
System: The UNT Digital Library
Meteorological database for the United States (open access)

Meteorological database for the United States

A meteorological database has been developed to aid in the prediction of indoor radon concentrations in the United States. The database contains predicted typical monthly meteorological statistics at the county level derived from hourly meteorological data from 208 (234 for precipitation) geographically distinct monitoring stations. Interpolation and extrapolation techniques were used to predict statistics for counties not containing a meteorological monitoring site. The LBNL database includes statistics for meteorological variables including dry-bulb temperature, dew-point temperature, barometric pressure, wind speed, wind direction, hours of precipitation, precipitation, and derived infiltration degree-days. The database consists of individual files of derived statistics for each weather variable and is potentially useful for indoor radon modeling as well as for other purposes. Each file contains data values for all 12 months and an aggregation of the 12 months up to a yearly statistic for all county centroids. A test was conducted to assess the quality of interpolated values. Examples showing the use of the database for mapping infiltration degree-days and an application of the database to a statistical correlation analysis attempting to find meteorological factors influencing indoor radon levels in the United States is discussed.
Date: April 1, 1996
Creator: Apte, M.G.; Nero, A.V. & Revzan, K.L.
System: The UNT Digital Library
Corrosion of target and structural materials in water irradiated by an 800 MeV proton beam (open access)

Corrosion of target and structural materials in water irradiated by an 800 MeV proton beam

Radiation enhanced, aqueous corrosion of solid neutron-targets such as tungsten or tantalum, or target cladding or structural materials such as superalloys and stainless steels, is a significant concern in accelerator-driven transmutation technologies. In this paper we briefly describe our current methods for control and in situ monitoring of corrosion in accelerator cooling water loops. Using floating, electrochemical impedance spectroscopy (EIS), we have measured the corrosion rates of aluminum 6061, copper, Inconel 718, and 304L stainless steel in the flow loop of a water target irradiated by a {mu}amp, 800 MeV proton beam. Impedance spectroscopy allows us to model the corrosion process of a material as an equivalent electrical circuit. Thus the polarization resistance, which is inversely proportional to the corrosion rate, can be extracted from the frequency response of a metal specimen. During a three month period, without the use of corrosion mitigation techniques, we observed increases of several orders of magnitude in the water conductivity and the corrosion rates. The increase in corrosion is at least partially attributed to a build up of peroxide in our pseudo-closed loop system. In this paper we also briefly describe our second generation experiments, scheduled to begin in late 1996. In these experiments …
Date: July 1, 1996
Creator: Butt, Darryl P.; Kanner, Gary S. & Lillard, R. Scott
System: The UNT Digital Library
Transition Form Factor gamma gamma* -> pi(sup)0 and QCD sum rules (open access)

Transition Form Factor gamma gamma* -> pi(sup)0 and QCD sum rules

We extend the QCD sum rule analysis of the form factor F(sub)(gamma*gamma* -> pi^0)(q(sub)1^2, q(sub)2^2) into the region of small virtuality of one of the photons:
Date: March 1, 1996
Creator: Radyushkin, Anatoly & Ruskov, R.
System: The UNT Digital Library
Target space supersymmetric sigma model techniques (open access)

Target space supersymmetric sigma model techniques

We briefly review the covariant formulation of the Green-Schwarz superstring by Berkovits, and describe how a detailed tree-level and one-loop analysis of this model leads, for the first time, to a derivation of the low-energy effective action of the heterotic superstring while keeping target-space supersymmetry manifest. The resulting low-energy theory is old-minimal supergravity coupled to tensor multiplet. The dilaton is part of the compensator multiplet.
Date: July 1, 1996
Creator: de Boer, Jan & Skenderis, Kostas
System: The UNT Digital Library
Anomalous U(1) and low-energy physics: the power of D-flatness and holomorphy (open access)

Anomalous U(1) and low-energy physics: the power of D-flatness and holomorphy

In models with an anomalous abelian symmetry broken at a very large scale, we study which requirements to impose on the anomalous charges in order to prevent standard model fields from acquiring large vacuum expectation values. The use of holomorphic invariants to study D-flat directions for the anomalous symmetry, proves to be a very powerful tool. We find that in order to forbid unphysical configurations at that scale, the superpotential must contain many interaction terms, including the usual Yukawa terms. Our analysis suggests that the anomalous charge of the {mu}-term is zero. It is remarkable that, together with the seesaw mechanism, and mass hierarchies, this implies a natural conservation of R-parity.
Date: December 1, 1996
Creator: Binetruy, P.; Irges, N.; Lavignac, S. & Ramond, P.
System: The UNT Digital Library
Two distinct phases of apoptosis in mammary gland involution: proteinase-independent and -dependent pathways (open access)

Two distinct phases of apoptosis in mammary gland involution: proteinase-independent and -dependent pathways

Postlactational involution of the mammary gland is characterized by two distinct physiological events: apoptosis of the secretory, epithelial cells undergoing programmed cell death, and proteolytic degradation of the mammary gland basement membrane. We examined the spatial and temporal patterns of apoptotic cells in relation to those of proteinases during involution of the BALB/c mouse mammary gland. Apoptosis was almost absent during lactation but became evident at day 2 of involution, when {beta}-casein gene expression was still high. Apoptotic cells were then seen at least up to day 8 of involution, when {beta}-casein gene expression was being extinguished. Expression of sulfated glycoprotein-2 (SGP-2), interleukin-1{beta} converting enzyme (ICE) and tissue inhibitor of metalloproteinases-1 was upregulated at day 2, when apoptotic cells were seen initially. Expression of the matrix metalloproteinases gelatinase A and stromelysin-1 and the serine proteinase urokinase-type plasminogen activator, which was low during lactation, was strongly upregulated in parallel starting at day 4 after weaning, coinciding with start of the collapse of the lobulo-alveolar structures and the intensive tissue remodeling in involution. The major sites of mRNA synthesis for these proteinases were fibroblast-like cells in the periductal stroma and stromal cells surrounding the collapsed alveoli, suggesting that the degradative phase of …
Date: January 1, 1996
Creator: Lund, Leif R; Romer, John; Thomasset, Nicole; Solberg, Helene; Pyke, Charles; Bissell, Mina J et al.
System: The UNT Digital Library
Evaluation of the graphite electrode arc melter for processing heterogeneous waste (open access)

Evaluation of the graphite electrode arc melter for processing heterogeneous waste

The U.S. Bureau of Mines (USBM) conducted a series of 4 demonstration melting tests in a 3-phase AC graphite electrode arc furnace at its Albany Research Center (ALRC) thermal treatment facility in Albany, Oregon (now part of the U.S. Department of Energy, DOE). The scope of these tests provides a unique opportunity to evaluate a single melting technology regarding its applicability to the treatment of several different heterogeneous mixed wastes. The current system can continuously process combustible-bearing wastes at feedrates to 682 kg/h (1,500 lb/h), continuously tap slag or glass, and intermittently tap metal products, and includes a close-coupled thermal oxidizer and air pollution control system (APCS). The 4 demonstration melting tests were conducted in cooperation with the American Society of Mechanical Engineers (ASME), the Idaho National Engineering Laboratory (INEL), and the Westinghouse Hanford Company (WHC).
Date: January 1, 1996
Creator: O'Connor, William K.; Turner, Paul C.; Soelberg, N. R. & Anderson, G. L.
System: The UNT Digital Library
Highly stable explicit technique for stiff reaction-transport PDEs (open access)

Highly stable explicit technique for stiff reaction-transport PDEs

The numerical simulation of chemically reacting flows is a topic that has attracted a great deal of current research. At the heart of numerical reactive flow simulations are large sets of coupled, nonlinear partial differential equations (PDEs). Due to the stiffness that is usually present, explicit time differencing schemes are not used despite their inherent simplicity and efficiency on parallel and vector machines, since these schemes require prohibitively small numerical stepsizes. Implicit time differencing schemes, although possessing good stability characteristics, introduce a great deal of computational overhead necessary to solve the simultaneous algebraic system at each timestep. This paper proposes an algorithm based on a preconditioned time differencing scheme. The algorithm is explicit and permits a large stable time step. A study of the algorithm's performance on a parallel architecture is presented.
Date: December 1, 1996
Creator: Aro, C. J., LLNL
System: The UNT Digital Library
ERC Program Overview (open access)

ERC Program Overview

The carbonate fuel cell promises highly efficient, cost-effective, environmentally superior power generation from pipeline natural gas, coal gas, biogas, and other gaseous and liquid fuels. ERC has been engaged in the development of this unique technology since the late 1970s, primarily focusing on the development of the Direct Fuel Cell (DFC) technology [1-6] pioneered by ERC. The DFC design incorporates the unique internal reforming feature which allows utilization of a hydrocarbon fuel directly in the fuel cell without requiring any external reforming reactor and associated heat exchange equipment. This approach provides upgrading of waste heat to chemical energy; thereby, it contributing to higher overall efficiency for conversion of fuel energy to electricity with low levels of environmental emissions. Among the internal reforming options, ERC has selected the Indirect Internal Reforming (IIR) - Direct Internal Reforming (DIR) combination as its baseline design. ERC plans to offer commercial DFC power plants in various sizes, initially focusing on the MW-scale units. The plan is to offer standardized, packaged MW-scale DFC power plants operating on natural gas or other hydrocarbon-containing fuels for commercial sale by the end of the decade. These power plants, which can be shop-fabricated and sited near the user, are ideally …
Date: August 1, 1996
Creator: Maru, H.; Farooque, M.; Carlson, G.; Patel, P.; Yuh, C.; Bentley, C. et al.
System: The UNT Digital Library
Application of Catalytic Extraction Processing to DOE Wastes (open access)

Application of Catalytic Extraction Processing to DOE Wastes

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Date: October 1, 1996
Creator: unknown
System: The UNT Digital Library
The effects of silicon doping on the performance of PMAN carbon anodes in Li-ion cells (open access)

The effects of silicon doping on the performance of PMAN carbon anodes in Li-ion cells

Carbons derived from polymethylacrylonitrile (PMAN) have been studied for use as intercalation anodes in Li-ion cells. The effect of Si doping upon the electrochemical performance of PMAN carbons was studied using tetravinylsilane (TVS) and tetramethysilane (TMS) as sources of Si during the formation of the PMAN precursors. The carbons were characterized by galvanostatic cycling, cyclic voltammetry, and complex impedance. The presence of 9 to 11 w/o Si in the PMAN lattice greatly increased the irreversible capacity of these materials.
Date: May 1, 1996
Creator: Guidotti, Ronald A.; Johnson, Bryan J. & Even, William, Jr.
System: The UNT Digital Library
Electrochemical impedance spectroscopy studies of lithium diffusion in doped manganese oxide (open access)

Electrochemical impedance spectroscopy studies of lithium diffusion in doped manganese oxide

Cathode performance is critical to lithium ion rechargeable battery performance; effects of doping lithium manganese oxide cathode materials on cathode performance are being investigated. In this paper, Li diffusion in Al-doped LiMn{sub 2}O{sub 4} was studied and found to be controlled by the quantity of Al dopant. Electrochemical cycling was conducted at 0.5mA/cm{sub 2}; electrochemical impedance spectra were taken at open circuit potential, with impedance being measured at 65 kHz-0.01 Hz. As the Al dopant level was increased, the Li diffusion rate decreased; this was attributed to the decreased lattice parameter of the doped oxide.
Date: June 1, 1996
Creator: Johnson, B. J.; Doughty, D. H.; Voigt, J. A. & Boyle, T. J.
System: The UNT Digital Library
Fast Wave Heating and Current Drive in DIII-D Discharges With Negative Central Shear (open access)

Fast Wave Heating and Current Drive in DIII-D Discharges With Negative Central Shear

The noninductive current driven by fast Alfven waves (FWCD) has been applied to discharges in DIII-D with negative central shear. Driven currents as high as 275 kA have been achieved with up to 3 MW of fast wave power with the efficiency and profile as predicted by theory-based modeling. When counter-current FWCD was applied to discharges with negative central shear, the negative shear was strengthened and prolonged, showing that FWCD can help to control the current profile in advanced tokamak discharges. Under some conditions in negative central shear, the plasma spontaneously makes a transition into a regime of improved performance, with a reduction in both the ion and the electron heat diffusivities. Up to 3 MW of fast wave power has been successfully coupled into H-mode discharges with large edge localized modes through use of an innovative decoupler/hybrid power splitter combination.
Date: October 1, 1996
Creator: Prater, R.; Austin, M. E. & Baity, F. W.
System: The UNT Digital Library
Getting to necessary and sufficient-developing accident scenarios for risk assessment (open access)

Getting to necessary and sufficient-developing accident scenarios for risk assessment

This paper presents a simple, systematic approach for developing accident scenarios using generic accident types. Result is a necessary and sufficient set of accident scenarios that can be used to establish the safety envelope for a facility or operation. Us of this approach along with the methodology of SAND95-0320 will yield more consistent accident analyses between facilities and provide a sound basis for allocating limited risk reduction resources.
Date: May 1, 1996
Creator: Mahn, Jeffrey A.
System: The UNT Digital Library
Nonlinear spatio-temporal interactions and neural connections in human vision using transient and M-sequence stimuli (open access)

Nonlinear spatio-temporal interactions and neural connections in human vision using transient and M-sequence stimuli

Reciprocal connections, in essence, are the dynamic wiring (connections) of the neural network circuitry. Given the high complexity of the neural circuitry in the human brain, it is quite a challenge to study the dynamic wiring of highly parallel and widely distributed neural networks. The measurements of stimulus evoked coherent oscillations provide indirect evidence of dynamic wiring. In this study, in addition to the coherent oscillation measurements, two more techniques are discussed for testing possible dynamic wiring: measurements of spatio-temporal interactions beyond the classical receptive fields, and neural structural testing using nonlinear systems analysis.
Date: February 1, 1996
Creator: Chen, H. W.; Aine, C. J.; Flynn, E. R. & Wood, C. C.
System: The UNT Digital Library