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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
Ordering of a prototypical conjugated molecular system during monolayer growth on the (1 x 2)- Au(110) surface (open access)

Ordering of a prototypical conjugated molecular system during monolayer growth on the (1 x 2)- Au(110) surface

Article on the ordering of a prototypical conjugated molecular system during monolayer growth on the (1x2)-Au(110) surface.
Date: 1996
Creator: Buongiorno Nardelli, Marco; Cvetko, D.; De Renzi, V.; Floreano, L.; Gotter, R.; Morgante, A. et al.
System: The UNT Digital Library
Training Employees With Disabilities: Strategies from Corporate Training (open access)

Training Employees With Disabilities: Strategies from Corporate Training

Article discussing strategies used by corporate trainers to effectively teach populations with disabilities in their corporate workplace.
Date: 1996
Creator: Allen, Jeff M. & Walker, Michelle
System: The UNT Digital Library
Strategic Planning of Technology for Education: A Beginning Framework (open access)

Strategic Planning of Technology for Education: A Beginning Framework

Article discussing strategic planning of technology for education and a beginning framework for future technology implementation in school districts.
Date: 1996
Creator: Allen, Jeff M.
System: The UNT Digital Library
Superconducting Magnets for a Muon Collider (open access)

Superconducting Magnets for a Muon Collider

None
Date: February 15, 1996
Creator: Green, Michael A.
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
Chemical hydrofracturing of the Hot Dry Rock reservoir (open access)

Chemical hydrofracturing of the Hot Dry Rock reservoir

The experimental study of the water-rock interaction shows that the secondary mineral assemblage depends on the water composition. For example, granite-pure water interaction produces zeolites (relatively low-dense, Mg-poor minerals), whereas seawater yields chlorites (high-dense, Mg-rich minerals). The reactions have volumetric effects from several % to 20 % in magnitude. Volume deformations in the heterogeneous matrix cause uneven mechanical strains. Reactions with the effect of about 0,1 vol.% may cause strains of the order of 100-1000 bars being enough for destruction of rocks. Signs and magnitudes of local volume changes depend on the mineral composition of the secondary assemblage. Hence, one can provide either healing or cracking of primary fractures, as desired, by changing the composition of water in the water-felsic rock system where some elements (Mg, Fe) are in lack. The techniques of "chemical hydrofracturing" looks promising as applied to a granite HDR massif. One can regulate the permeability of fractured flow paths by changing in concord the composition and pressure of the injected water. This approach should promote efficient extraction of the petrothermal energy.
Date: January 24, 1996
Creator: Yakovlev, Leonid
System: The UNT Digital Library
Inverse Free Electron Laser Acceleration with a Square Wave Wiggler (open access)

Inverse Free Electron Laser Acceleration with a Square Wave Wiggler

None
Date: August 19, 1996
Creator: Parsa, Z. & Pato, M. P.
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
DOE pollution prevention in the 21st century. Proceedings (open access)

DOE pollution prevention in the 21st century. Proceedings

This CD-ROM contains the proceedings from the DOE Pollution Prevention in the 21st Century Conference XII held July 9-11, 1996. Topics included model facilities, federal and NEPA stakeholders, microchemistry, source 4 solvents and reduction, education and outreach planning, return on investment, energy management, decontamination and decommissioning, planning and regulations, environmental restoration, solid waste, recycling, affirmative procurement in the executive branch, construction and demolition, international and ISO 14000, and poster sessions.
Date: December 31, 1996
Creator: unknown
System: The UNT Digital Library
A Count Rate Based Contamination Control Standard for Electron Accelerators (open access)

A Count Rate Based Contamination Control Standard for Electron Accelerators

Accelerators of sufficient energy and particle fluence can produce radioactivity as an unwanted byproduct. The radioactivity is typically imbedded in structural materials but may also be removable from surfaces. Many of these radionuclides decay by positron emission or electron capture; they often have long half lives and produce photons of low energy and yield making detection by standard devices difficult. The contamination control limit used throughout the US nuclear industry and the Department of Energy is 1,000 disintegrations per minute. This limit is based on the detection threshold of pancake type Geiger-Mueller probes for radionuclides of relatively high radiotoxicity, such as cobalt-60. Several radionuclides of concern at a high energy electron accelerator are compared in terms of radiotoxicity with radionuclides commonly found in the nuclear industry. Based on this comparison, a count-rate based contamination control limit and associated measurement strategy is proposed which provides adequate detection of contamination at accelerators without an increase in risk.
Date: December 31, 1996
Creator: May, R. T. & Schwahn, S. O.
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
Superfluid Performance of Tevatron IR Quad Heaters (open access)

Superfluid Performance of Tevatron IR Quad Heaters

A collaborative team from the two laboratories measured the performance of a Tevatron Interaction region (IR) quadrupole at temperatures from 1.8 K to 4.4 K. These studies included measurement of their performance as a function of temperature as well as measurement of the effectiveness of the protection heaters. Heater diffusion times were measured for various temperatures, current levels, and power densities. These results and their implications on the design of magnet protection systems and magnet design operating in this temperature range will be discussed.
Date: December 12, 1996
Creator: Lietzke, A.; McInturff, A. D. & Scanlan, R. M.
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
PUREX transition project case study (open access)

PUREX transition project case study

In December 1992, the US Department of Energy (DOE) directed that the Plutonium-Uranium Extraction (PUREX) Plant be shut down and deactivated because it was no longer needed to support the nation`s production of weapons-grade plutonium. The PUREX/UO{sub 2} Deactivation Project will establish a safe and environmentally secure configuration for the facility and preserve that configuration for 10 years. The 10-year span is used to predict future maintenance requirements and represents the estimated time needed to define, authorize, and initiate the follow-on decontamination and decommissioning activities. Accomplishing the deactivation project involves many activities. Removing major hazards, such as excess chemicals, spent fuel, and residual plutonium are major goals of the project. The scope of the PUREX Transition Project is described within.
Date: April 15, 1996
Creator: Jasen, W. G.
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
Wakimoto realizations of current algebras: an explicit construction (open access)

Wakimoto realizations of current algebras: an explicit construction

A generalized Wakimoto realization of $\widehat\cal G_K$ can be associated with each parabolic subalgebra $\cal P=(\cal G_0 +\cal G_+)$ of a simple Lie algebra $\cal G$ according to an earlier proposal by Feigin and Frenkel. In this paper the proposal is made explicit by developing the construction of Wakimoto realizations from a simple but unconventional viewpoint. An explicit formula is derived for the Wakimoto current first at the Poisson bracket level by Hamiltonian symmetry reduction of the WZNW model. The quantization is then performed by normal ordering the classical formula and determining the required quantum correction for it to generate $\widehat\cal G_K$ by means of commutators. The affine-Sugawara stress-energy tensor is verified to have the expected quadratic form in the constituents, which are symplectic bosons belonging to $\cal G_+$ and a current belonging to $\cal G_0$. The quantization requires a choice of special polynomial coordinates on the big cell of the flag manifold $P\backslash G$. The effect of this choice is investigated in detail by constructing quantum coordinate transformations. Finally, the explicit form of the screening charges for each generalized Wakimoto realization is determined, and some applications are briefly discussed.
Date: November 12, 1996
Creator: de Boer, Jan & Feher, Laszlo
System: The UNT Digital Library
Will at least one of the Higgs bosons of the next-to-minimal supersymmetric extension of the standard model be observable at LEP2 or the LHC? (open access)

Will at least one of the Higgs bosons of the next-to-minimal supersymmetric extension of the standard model be observable at LEP2 or the LHC?

We demonstrate that there are regions of parameter space in the next-to-minimal (i.e. two-Higgs-doublet, one-Higgs-singlet superfield) supersymmetric extension of the SM for which none of the Higgs bosons are observable either at LEP2 with $\sqrt{s}=192 GeV$ and an integrated luminosity of $L=1000inverse pb$ or at the LHC with $L=600 inverse fb$.
Date: June 24, 1996
Creator: Gunion, John F.; Haber, Howard E. & Moroi, Takeo
System: The UNT Digital Library