Resource Type

Quench observation using quench antennas on RHIC IR quadrupole magnets (open access)

Quench observation using quench antennas on RHIC IR quadrupole magnets

Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals.
Date: July 1995
Creator: Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J. & Wanderer, P.
System: The UNT Digital Library
The magnet system of the Relativistic Heavy Ion Collider (RHIC) (open access)

The magnet system of the Relativistic Heavy Ion Collider (RHIC)

The Relativistic Heavy Ion Collider now under construction at Brookhaven National Laboratory (BNL) is a colliding ring accelerator to be completed in 1999. Through collisions of heavy ions it is hoped to observe the creation of matter at extremely high temperatures and densities, similar to what may have occurred in the original "Big Bang." The collider rings will consist of 1740 superconducting magnet elements. Some of elements are being manufactured by industrial partners (Northrop Grumman and Everson Electric). Others are being constructed or assembled at BNL. A description is given of the magnet designs, the plan for manufacturing and test results. In the manufacturing of the magnets, emphasis has been placed on uniformity of their performance and on quality. Results so far indicate that this emphasis has been very successful.
Date: July 1995
Creator: Greene, A.; Anerella, M. & Cozzolino, J.
System: The UNT Digital Library
Diphoton production in p{bar p} collisions at {radical}s = 1.8 TeV (open access)

Diphoton production in p{bar p} collisions at {radical}s = 1.8 TeV

We present measurements of the inclusive {gamma}{gamma} cross section (as a function of invariant mass and photon {epsilon}{sub {tau}}), in p{bar p} collisions at {radical}s = 1.8 TeV, made using the D0 detector at the Fermilab Tevatron collider. The next is leading order (NLO) QCD prediction is found to be in good agreement with the data. The effects of invariant mass and diphoton balance cuts, which test the next-to-leading order contributions to the cross section, are investigated. We also compare the distribution of {kappa}{sub {tau}} between samples of diphotons and highly electromagnetic jets, and find that the NLO QCD prediction models the shape of the {gamma}{gamma} {kappa}{sub {tau}} distribution quite well.
Date: July 1, 1995
Creator: Abachi, S.
System: The UNT Digital Library
Integrated models for plasma/material interaction during loss of plasma confinement. (open access)

Integrated models for plasma/material interaction during loss of plasma confinement.

A comprehensive computer package, High Energy Interaction with General Heterogeneous Target Systems (HEIGHTS), has been developed to evaluate the damage incurred on plasma-facing materials during loss of plasma confinement. The HEIGHTS package consists of several integrated computer models that follow the start of a plasma disruption at the scrape-off layer (SOL) through the transport of the eroded debris and splashed target materials to nearby locations as a result of the energy deposited. The package includes new models to study turbulent plasma behavior in the SOL and predicts the plasma parameters and conditions at the divertor plate. Full two-dimensional comprehensive radiation magnetohydrodynamic models are coupled with target thermodynamics and liquid hydrodynamics to evaluate the integrated response of plasma-facing materials. A brief description of the HEIGHTS package and its capabilities are given in this work with emphasis on turbulent plasma behavior in the SOL during disruptions.
Date: July 29, 1998
Creator: Hassanein, A.
System: The UNT Digital Library
Progress and future plans for MPC and A at Chelyabinsk-70 (open access)

Progress and future plans for MPC and A at Chelyabinsk-70

This paper describes that portion of the Nuclear Materials Protection, Control, and Accounting (MPC and A) program that is directed specifically to the needs of the All Russian Scientific Research Institute of Technical Physics (VNIITF), also called Chelyabinsk-70. Chelyabinsk-70 is located in the Ural Mountains, approximately 2000 km east of Moscow and 100 km south of Ekaterinburg. The MPC and A work that has been completed, is underway and planned at the facility will be described. During the first two years of the VNIITF project, emphasis was on the Pulse Research Reactor Facility (PRR), which contains one metal and two liquid pulse reactors and associated nuclear material storage rooms and a control center. A commissioning of the PRR was held in May of 1998. With the completion of the MPC and A work in the PRR, new physical protection work is focusing on other areas. VNIITF-wide physical protection initiatives underway include access control and computerized badging systems, and a central MPC and A control system. Measured physical inventory taking is a high priority for the VNIITF Project Team. A VNIITF-wide computerized accounting system is also being developed for the large and diverse inventory of nuclear material subject to MPC and …
Date: July 8, 1999
Creator: Apt, K.; Blasy, J.; Bukin, D.; Cahalane, P.; Churikov, Y.; Curtis, D. et al.
System: The UNT Digital Library
An update on projection methods for transient incompressible viscous flow (open access)

An update on projection methods for transient incompressible viscous flow

Introduced in 1990 was the biharmonic equation (for the pressure) and the concomitant biharmonic miracle when transient incompressible viscous flow is solved approximately by a projection method. Herein is introduced the biharmonic catastrophe that sometimes occurs with these same projection methods.
Date: July 1, 1995
Creator: Gresho, P.M. & Chan, S.T.
System: The UNT Digital Library
A novel condenser for EUV lithography ring-field projection optics (open access)

A novel condenser for EUV lithography ring-field projection optics

A condenser for a ring-field extreme ultra-violet (EUV) projection lithography camera is presented. The condenser consists of a gently undulating mirror, that we refer to as a ripple plate, and which is illuminated by a collimated beam at grazing incidence. The light is incident along the ripples rather than across them, so that the incident beam is reflected onto a cone and subsequently focused on to the arc of the ring field. A quasistationary illumination is achieved, since any one field point receives light from points on the ripples, which are distributed throughout the condenser pupil. The design concept can easily be applied to illuminate projection cameras with various ring-field and numerical aperture specifications. Ray-tracing results are presented of a condenser for a 0.25 NA EUV projection camera.
Date: July 15, 1999
Creator: Chapman, H. & Nugent, K. A.
System: The UNT Digital Library
Neutron spectroscopy of high-density amorphous ice. (open access)

Neutron spectroscopy of high-density amorphous ice.

Vibrational spectra of high-density amorphous ice (hda-ice) for H{sub 2}O and D{sub 2}O samples were measured by inelastic neutron scattering. The measured spectra of hda-ice are closer to those for high-pressure phase ice-VI, but not for low-density ice-Ih. This result suggests that similar to ice-VI the structure of hda-ice should consist of two interpenetrating hydrogen-bonded networks having no hydrogen bonds between themselves.
Date: July 17, 1998
Creator: Kolesnikov, A. I.
System: The UNT Digital Library
Production of heavy quark states at CDF (open access)

Production of heavy quark states at CDF

In this paper the author presents results on quarkonia production, B-meson production and b{bar b} correlations in p{bar p} collisions at {radical}s = 1.8 TeV. These results were obtained from data taken with the CDF detector at Fermilab. The author covers recently completed analyses of the 1992-95 collider run. Prospects for the near and more distant future are also discussed.
Date: July 1, 1995
Creator: Papadimitriou, V.
System: The UNT Digital Library
Plasma Rotation, Dynamo, and Nonlinear Coupling in the Reversed Field Pinch (open access)

Plasma Rotation, Dynamo, and Nonlinear Coupling in the Reversed Field Pinch

Two important effects of MHD fluctuations in the RFP and tokamak are current generation (the dynamo effect) and mode locking. In the T1 and MST RFP experiments new results reveal the mode dynamics underlying these phenomena. In T1 the effect of specific magnetic Fourier modes on the current density profile is evident. In MST, the MHD dynamo term ({delta}v x {delta}B) is measured in the plasma edge, and found to account for the time dependence of the edge current throughout a sawtooth cycle. As edge resistivity is increased in T1 the fluctuation amplitude increases to maintain the dynamo-driven current, as expected from MHD computation. The modes responsible for the dynamo often lock to the local magnetic field error at the vertical cut in MST. The plasma rotation velocity has been measured with a fast Doppler spectrometer to a time resolution of 1 {mu}s. The plasma rotation and mode phase velocity are remarkably well-correlated, with both slowing, in the presence of an impulsive field error, in a 100 {mu}s timescale.
Date: July 1, 1995
Creator: Prager, S. C.; Almagri, A. F. & Cekic, M.
System: The UNT Digital Library
Above and beyond basic public participation (open access)

Above and beyond basic public participation

This paper evolved out of a discussion about public participation as it is currently being brought to the fore-front of clean-up activities at hazardous waste sites. There exists much official and unofficial documentation pertaining to the need for public involvement. The purposes for public involvement efforts in Environmental Restoration are: to enable substantive input to the clean-up process; methods for establishing formal, and now informal, mechanisms for public input and awareness of on-going facility activities; and the opening of better channels for communication and conflict resolution between the public and the facility. This presentation will briefly outline the regulatory approach for public outreach because many of these terms are used with such frequency, their meanings tend to get forgotten or misconstrued. Then, the authors will critique the most common methods for conducting public involvement as attempted through advisory boards and public meetings. For illustrative purposes, they will be referring to the site they are most familiar with, which is Los Alamos National Laboratory (LANL).
Date: July 1, 1995
Creator: Mathai, L. P.; Lefkoff, M. S. & Kelly, E. J.
System: The UNT Digital Library
Black-Hole Astrophysics (open access)

Black-Hole Astrophysics

Black-hole astrophysics is not just the investigation of yet another, even if extremely remarkable type of celestial body, but a test of the correctness of the understanding of the very properties of space and time in very strong gravitational fields. Physicists` excitement at this new prospect for testing theories of fundamental processes is matched by that of astronomers at the possibility to discover and study a new and dramatically different kind of astronomical object. Here the authors review the currently known ways that black holes can be identified by their effects on their neighborhood--since, of course, the hole itself does not yield any direct evidence of its existence or information about its properties. The two most important empirical considerations are determination of masses, or lower limits thereof, of unseen companions in binary star systems, and measurement of luminosity fluctuations on very short time scales.
Date: July 1, 1995
Creator: Bender, P.; Bloom, E. & Cominsky, L.
System: The UNT Digital Library
Predicting the Future at Yucca Mountain (open access)

Predicting the Future at Yucca Mountain

This paper summarizes a climate-prediction model funded by the DOE for the Yucca Mountain nuclear waste repository. Several articles in the open literature attest to the effects of the Global Ocean Conveyor upon paleoclimate, specifically entrance and exit from the ice age. The data shows that these millennial-scale effects are duplicated on the microscale of years to decades. This work also identifies how man may have influenced the Conveyor, affecting global cooling and warming for 2,000 years.
Date: July 1, 1999
Creator: Wilson, J. R.
System: The UNT Digital Library
Analysis of releases due to drilling at the potential Yucca Mountain repository (open access)

Analysis of releases due to drilling at the potential Yucca Mountain repository

Human Instrusion into the potential repository at Yucca Mountain, Nevada, was modeled in the Total-System Performance Assessment (``TSPA-91``) recently completed for the Yucca Mountain Site Characterization Project Office of the DOE. The scenario model assumed that the repository would be penetrated at random locations by a number of boreholes drilled using twentieth-century rotary drilling techniques.
Date: July 1, 1993
Creator: Barnard, R.W.
System: The UNT Digital Library
Physics prospects with the upgraded CDF detector (open access)

Physics prospects with the upgraded CDF detector

The CDF detector is being extensively upgraded for Fermilab Tevatron Run II, which is scheduled to begin in 1999. This talk describes the planned detector upgrades. The power of the upgraded detector is illustrated by showing the expected precision of several physics measurements that will be made with the Run II data: the top mass, the W mass, BR(t{yields}Wb), and the CP violation parameters sin(2{alpha}) and sin(2{beta}).
Date: July 1, 1995
Creator: Hylen, J.
System: The UNT Digital Library
Forecast of criticality experiments and experimental programs needed to support nuclear operations in the United States of America: 1994-1999 (open access)

Forecast of criticality experiments and experimental programs needed to support nuclear operations in the United States of America: 1994-1999

This Forecast is generated by the Chair of the Experiment Needs Identification Workgroup (ENIWG), with input from Department of Energy and the nuclear community. One of the current concerns addressed by ENIWG was the Defense Nuclear Facilities Safety Board`s Recommendation 93-2. This Recommendation delineated the need for a critical experimental capability, which includes (1) a program of general-purpose experiments, (2) improving the information base, and (3) ongoing departmental programs. The nuclear community also recognizes the importance of criticality theory, which, as a stepping stone to computational analysis and safety code development, needs to be benchmarked against well-characterized critical experiments. A summary projection of the Department`s needs with respect to criticality information includes (1) hands-on training, (2) criticality and nuclear data, (3) detector systems, (4) uranium- and plutonium-based reactors, and (5) accident analysis. The Workgroup has evaluated, prioritized, and categorized each proposed experiment and program. Transportation/Applications is a new category intended to cover the areas of storage, training, emergency response, and standards. This category has the highest number of priority-1 experiments (nine). Facilities capable of performing experiments include the Los Alamos Critical Experiment Facility (LACEF) along with Area V at Sandia National Laboratory. The LACEF continues to house the most significant …
Date: July 1, 1995
Creator: Rutherford, D.
System: The UNT Digital Library
Modeling LNAPL transport in the Vadose Zone (open access)

Modeling LNAPL transport in the Vadose Zone

Groundwater contamination is an ever growing problem. In particular, problems associated with light non-aqueous phase liquids (LNAPLs) such as gasoline, diesel fuel, and jet fuels are becoming more common. This paper presents the development and application of an analytical model for predicting LNAPL concentrations at the water table. Based on the volume of the spill, the model has two parts: a pancake model for predicting the behavior of the LNAPL if the spill volume is large enough to reach the water table; and an advection/dispersion model that assumes that the LNAPL does not reach the water table as a slug, but creates a contaminated soil layer from which soluble LNAPL components can be mobilized and transported vertically downward while undergoing advection, dispersion, sorption, volatilization, and biodegradation. Maximum and current concentrations are calculated at the water table for the pancake model using a solubility-limited approach, and an analytical expression derived using Laplace transforms for the advection/dispersion model. The behavior and sensitivity of the model is evaluated for a hypothetical site using an LNAPL having ten components that represent a cross section of organic compounds commonly found in spills including BTEX, branch alkanes, and polynuclear aromatic hydrocarbons. Results of the study indicate …
Date: July 1, 1995
Creator: Tomasko, D. & Butler, J.P.
System: The UNT Digital Library
Development of stochastic indicator models of lithology, Yucca Mountain, Nevada (open access)

Development of stochastic indicator models of lithology, Yucca Mountain, Nevada

Indicator geostatistical techniques have been used to produce a number of fully three-dimensional stochastic simulations of large-scale lithologic categories at the Yucca Mountain site. Each realization reproduces the available drill hole data used to condition the simulation. Information is propagated away from each point of observation in accordance with a mathematical model of spatial continuity inferred through soft data taken from published geologic cross sections. Variations among the simulated models collectively represent uncertainty in the lithology at unsampled locations. These stochastic models succeed in capturing many major features of welded-nonwelded lithologic framework of Yucca Mountain. However, contacts between welded and nonwelded rock types for individual simulations appear more complex than suggested by field observation, and a number of probable numerical artifacts exist in these models. Many of the apparent discrepancies between the simulated models and the general geology of Yucca Mountain represent characterization uncertainty, and can be traced to the sparse site data used to condition the simulations. Several vertical stratigraphic columns have been extracted from the three-dimensional stochastic models for use in simplified total-system performance assessment exercises. Simple, manual adjustments are required to eliminate the more obvious simulation artifacts and to impose a secondary set of deterministic geologic features …
Date: July 1, 1994
Creator: Rautman, C.A. & Robey, T.H.
System: The UNT Digital Library
Plutonium concentrations in airborne soil at Rocky Flats and Hanford (open access)

Plutonium concentrations in airborne soil at Rocky Flats and Hanford

The objective of this paper is to summarize measured resuspension concentrations and to consider the implications of these results. In these experiments, airborne concentrations were measured as functions of wind speed, airborne particle size, wind direction, and the collected-plutonium and other nuclides per gram of airborne soil. Airborne radionuclides were normalized by the total amount of airborne solids to relate concentration per gram of airborne solid to concentration per gram of radionuclide on the ground.
Date: July 1, 1977
Creator: Sehmel, G. A.
System: The UNT Digital Library
Can solid-state laser technology serve usefully beyond fusion ignition facilities? (open access)

Can solid-state laser technology serve usefully beyond fusion ignition facilities?

We have explored the major technical and conceptual issues relating to the suitability of a diode-pumped solid state laser as a driver for an inertial fusion energy power plant. While solid state lasers have long served as the workhorse of inertial confinement fusion physics studies, the deployment of a driver possessing adequate efficiency, reliability, and repetition rate for inertial fusion energy requires the implementation of several technical innovations discussed in this article.
Date: July 28, 1995
Creator: Payne, S. A.; Powell, H. T. & Krupke, W. F.
System: The UNT Digital Library
Programmable applications in a heterogeneous and concurrent environment (open access)

Programmable applications in a heterogeneous and concurrent environment

Equipe Basis (EB) is a new system for programmable applications which is under development at Lawrence Livermore Laboratory. EB is designed to permit user control of teams of interconnecting processes in a heterogeneous environment. Current systems work with programs written in Fortran or C on a single processor. The programs of the future will be in many languages and distributed over many processors. The object-oriented kernel can communicate data and commands between processes that are unaware of each other`s inner structure. The programming language, Eiffel, is described. This document consists of extensive viewgraphs.
Date: July 21, 1995
Creator: Dubois, P.F.
System: The UNT Digital Library
Estimating environmental benefits of energy programs (open access)

Estimating environmental benefits of energy programs

Three national reporting programs that either collect or report information on energy savings and the associated emissions reductions from DSM programs are the Conservation Verification Protocols (CVP), the Greenhouse Gas Voluntary Reporting Program (VRP), and the Green Lights Program. The CVP were enacted to report the atmospheric emissions reductions of S0{sub 2} and N0{sub 2}. The VRP was mandated in the Energy Policy Act of 1992 (EPAct) Section 1605(b) to report CO{sub 2}, emissions reductions. Green Lights is a program designed to reduce emissions by encouraging energy-efficient lighting. In this paper we concentrate on how the verification methods, default emission factors and reporting mechanisms affect the accuracy of the reported energy and emissions savings. Additionally, we focus on the dynamic nature of predicted emissions reductions to gauge the accuracy of predictions over time. If conservation programs are designed to affect existing powerplants, if no load growth is anticipated, and if existing plants will not require replacement, a simple static analysis based on an existing resource mix may be acceptable. This approach is enhanced by defining base case, intermediate, and peak resources. However, if today`s decisions will affect tomorrow`s resource decisions, or if the estimates will be used to establish important …
Date: July 1, 1995
Creator: Baechler, M. C. & Schrock, D. W.
System: The UNT Digital Library
Ion-association: Models and thermodynamics (open access)

Ion-association: Models and thermodynamics

Association reactions are an important class for probing ion-water and water-water interactions. A review of some earlier results led to a model of ion-association reactions discussed by Mesmer et al. in Activity Coefficients of Electrolyte Solutions in 1991. Additional results especially from electrical conductance studies on acids and salts will be discussed. There is mounting evidence consistent with the general observations regarding the temperature and pressure dependencies for thermodynamic quantities for association reactions seen earlier including the driving force, T{Delta}S, that originates from the release of ion hydrate waters when pairing occurs. The density model for log K{sub A} serves well as a simple representation of the strong variation with temperature and pressure seen for these reactions. The decrease in solvent structure with increasing temperature and the increasing range of the ion-dipole interactions for hydrated ions (with decreasing dielectric constant) are thought to be the principal factors accounting for the dramatic trends seen for the thermodynamic quantities. Some discussion will be given of the simplicity found for the T-P dependencies for {delta}U{sub v} and {delta}C{sub v}, the changes in internal energy and heat capacity on a constant volume basis.
Date: July 1, 1995
Creator: Mesmer, R. E.; Ho, P. C.; Holmes, H. F.; Palmer, D. A. & Simonson, J. M.
System: The UNT Digital Library
Optical scatter as a diagnostic tool for studying bulk defects which cause laser damage in conventional and rapid growth KP and DKDP (open access)

Optical scatter as a diagnostic tool for studying bulk defects which cause laser damage in conventional and rapid growth KP and DKDP

Single crystals of KH{sub 2}PO{sub 4} (KDP) and (D{sub x}H{sub 1-x}){sub 2}PO{sub 4} (DKDP) will be used for frequency conversion and as part of a large aperture optical switch in the proposed National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL). These crystals must have good optical properties and high laser damage thresholds. Currently these crystals have a lower laser damage threshold than other optical materials in the laser chain which has forced designers to limit the output fluence of the NIF in order to avoid damaging the crystals. Furthermore, while more efficient frequency conversion schemes are being explored both theoretically and experimentally, the advantages of these schemes can not be fully realized unless the damage thresholds of the conversion crystals are increased. Over the past decade, LLNL has generated an extensive data base on the laser damage in KDP and DKDP crystals both at the first and third harmonics of Nd-YAG. While the damage thresholds of these crystals have increased over this time period due, in part, to better filtration of the growth solution, the damage thresholds of the best crystals are still far below what is expected from theoretical limits calculated from the band structure of …
Date: July 10, 1995
Creator: Woods, B.; Runkel, M. & Yan, M.
System: The UNT Digital Library