Physics possibilities at LHC/SSC (open access)

Physics possibilities at LHC/SSC

This document reviews some recent work on physics simulations for SSC/LHC. Included are reviews of some of the recent developments in physics simulations for the SSC/LHC and comments upon the requirements that are placed upon detectors by the need to extract specific physics signatures. The material in the various EOI/LOI documents submitted to the SCC Laboratory and the work done at the Aachen LHC workshop are discussed. In the following discussion 1 SSC (LHC) year corresponds to an integrated luminosity of 10 (100) fb{sup {minus}1}. 41 refs., 14 figs.
Date: April 25, 1991
Creator: Hinchliffe, I.
System: The UNT Digital Library
Development of beam position monitors for heavy ion recirculators (open access)

Development of beam position monitors for heavy ion recirculators

Work is underway at the Lawrence Livermore National Laboratory to design and build a small-scale, heavy ion recirculating induction accelerator. An essential part of this design work is the development of small nonintercepting diagnostics to measure beam current and position. This paper describes some of this work, with particular emphasis on the development of a small capacitive probe beam position monitor to resolve beam position to the 100 {mu}m level in a 6 cm diameter beam pipe. Initial measured results with an 80 keV potassium ion beam are presented.
Date: April 25, 1995
Creator: Deadrick, F. J.; Barnard, J. J.; Fessenden, T. J.; Meridith, J. W. & Rintamaki, J.
System: The UNT Digital Library
Health and safety guide for inorganic compounds and metals used in the fabrication of superconductive alloys (open access)

Health and safety guide for inorganic compounds and metals used in the fabrication of superconductive alloys

This health and safety guide was written to satisfy two objectives: to summarize the toxicity of metals and alloys used in superconductivity for the benefit of those who work with these materials, and to summarize and describes the basic principles of a highly technical field from a health and safety point-of-view for the benefit of health professionals. The guide begins with a profile of the superconductivity industry, including a list of current and potential applications, a literature review of the market potential, and summary of the current industry status. The body of the paper provides a toxicity and hazard summary for 50 metals, alloys and metal oxides used in superconductivity. The toxicity and hazard summary for all 50 compounds includes: occupational exposure limits, explosiveness and flammability potential, LD{sub 50}'s, chemical and physical properties, incompatibilities and reactivities, recommended personal protective equipment, symptoms of acute and chronic exposure, target organs and toxic effects, and steps for emergency first aid. Finally, a discussion of general occupational hygiene principles is provided, with emphasis on how these principles apply to the unique field of superconductivity. 41 refs.
Date: April 25, 1990
Creator: Arnold, S. D. & Talley, G. M.
System: The UNT Digital Library
Status of the Relativistic Heavy Ion Collider (open access)

Status of the Relativistic Heavy Ion Collider

Accelerator Physics issues, such as the dynamical aperture, the beam lifetime and the current--intensity limitation are carefully studied for the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The single layer superconducting magnets, of 8 cm coil inner diameter, satisfying the beam stability requirements have also been successfully tested. The proposal has generated wide spread interest in the particle and nuclear physics. 1 ref., 4 figs., 3 tabs.
Date: April 25, 1990
Creator: Lee, S. Y.
System: The UNT Digital Library
A Computational Study of the Reactions of Atomic Hydrogen with Fluoromethanes: Kinetics and Product Channels (open access)

A Computational Study of the Reactions of Atomic Hydrogen with Fluoromethanes: Kinetics and Product Channels

This article discusses a computational study of the reactions of atomic hydrogen with fluoromethanes and kinetics and product channels.
Date: April 25, 1997
Creator: Berry, Rajiv; Ehlers, C. J.; Burgess, Donald R.; Zachariah, Michael Russel, 1957- & Marshall, Paul
System: The UNT Digital Library
Hysteresis in Thin-Film Rechargeable Lithium Batteries (open access)

Hysteresis in Thin-Film Rechargeable Lithium Batteries

Discharge - charge cycling of thin-film rechargeable lithium batteries with an amorphous or nanocrystalline LiXMn2.Y04 cathode reveals evidence for a true hysteresis in the lithium insertion reaction. This is compared with an apparent hysteresis attributed to a kinetically hindered phase transition near 3 V for batteries with either a crystalline or a nanocrystalline LiJ@Yo4 cathode.
Date: April 25, 1999
Creator: Bates, J. B.; Dudney, N. J.; Evans, C. D. & Hart, F. X.
System: The UNT Digital Library
Can Cavitation Be Anticipated? (open access)

Can Cavitation Be Anticipated?

The major problem with cavitation in pumps and hydraulic systems is that there is no effective (conventional) method for detecting or predicting its inception. The traditional method of recognizing cavitation in a pump is to declare the event occurring when the total head drops by some arbitrary value (typically 3%) in response to a pressure reduction at the pump inlet. However, the device is already seriously cavitating when this happens. What is actually needed is a practical method to detect impending rather than incipient cavitation. Whereas the detection of incipient cavitation requires the detection of features just after cavitation starts, the anticipation of cavitation requires the detection and identification of precursor features just before it begins. Two recent advances that make this detection possible. The first is acoustic sensors with a bandwidth of 1 MHz and a dynamic range of 80 dB that preserve the fine details of the features when subjected to coarse vibrations. The second is the application of Bayesian parameter estimation which makes it possible to separate weak signals, such as those present in cavitation precursors, from strong signals, such as pump vibration. Bayesian parameter estimation derives a model based on cavitation hydrodynamics and produces a figure …
Date: April 25, 1999
Creator: Allgood, G. O.; Dress, W. B.; Hylton, J. O. & Kercel, S. W.
System: The UNT Digital Library
Diamond switches for high temperature electronics (open access)

Diamond switches for high temperature electronics

Diamond switches are well suited for use in high temperature electronics. Laboratory feasibility of diamond switching at 1 kV and 18 A was demonstrated. DC blocking voltages up to 1 kV were demonstrated. A 50 {Omega} load line was switched using a diamond switch, with switch on-state resistivity {approx}7 {Omega}-cm. An electron beam, {approx}150 keV energy, {approx}2 {mu}s full width at half maximum was used to control the 5 mm x 5 mm x 100 {mu}m thick diamond switch. The conduction current temporal history mimics that of the electron beam. These data were taken at room temperature.
Date: April 25, 1996
Creator: Prasad, R. R.; Rondeau, G. & Qi, Niansheng
System: The UNT Digital Library
Composite Dielectric Materials for Electrical Switching (open access)

Composite Dielectric Materials for Electrical Switching

Composites that consist of a dielectric host containing a particulate conductor as a second phase are of interest for electrical switching applications. Such composites are "smart" materials that can function as either voltage or current limiters, and the difference in fimction depends largely upon whether the dielectric is filled to below or above the percolation threshold. It also is possible to combine current and voltage limiting in a single composite to make a "super-smart" material.
Date: April 25, 1999
Creator: Modine, F.A.
System: The UNT Digital Library
Characterization of third-harmonic target plane irradiance on the National Ignition Facility Beamlet demonstration project (open access)

Characterization of third-harmonic target plane irradiance on the National Ignition Facility Beamlet demonstration project

The Beamlet laser is a single-aperture prototype for the National Ignition Facility (NIF). We have recently installed and activated a 55 m{sup 3} vacuum vessel and associated diagnostic package at the output of the Beamlet that we are using to characterize target plane irradiance at high power. Measurements obtained both with and without a kinoform diffractive optic are reported. Dependences on critical laser parameters including output power, spatial filtering, and wavefront correction are discussed and compared with simulations.
Date: April 25, 1997
Creator: Wegner, P. J.; Van Wonterghem, B. M.; Dixit, S. N.; Henesian, M. A.; Barker, C. E.; Thompson, C. E. et al.
System: The UNT Digital Library
Pattern of Thermal Fluctuations in a Recovery Boiler Floor (open access)

Pattern of Thermal Fluctuations in a Recovery Boiler Floor

The floor of a black liquor recovey boiler at a mill in central Canada has experienced cracking and delamination of the composite tubing near the spout wall and deformation of the floor panels that is most severe in the vicinity of the spout wall. One possible explanation for the observed damage is impacts of salt cake falling from the convective section onto the floor. In order to determine if such impacts do occur, strain gauges and thermocouples were installed on the boiler floor in areas where cracking and deformation were most frequent. The data obtained from these instruments indicate that brief, sudden temperature fluctuations do occur, and changes in the strain experienced by the affected tube occur simultaneously. These fluctuations appear to occur less often along the spout wall and more frequently with increasing distance from the wall. The frequency of these temperature fluctuations is insufficient for thermal fatigue to be the sole cause of the cracking observed on the tubes, but the data are consistent with what might be expected from pieces of falling salt cake.
Date: April 25, 1999
Creator: Abdullah, Z.; Gorog, J. P.; Keiser, J. R.; Meyers, L. E. & Swindeman, R. W.
System: The UNT Digital Library
Intermetallic-Based High-Temperature Materials (open access)

Intermetallic-Based High-Temperature Materials

The intermetallic-based alloys for high-temperature applications are introduced. General characteristics of intermetallics are followed by identification of nickel and iron aluminides as the most practical alloys for commercial applications. An overview of the alloy compositions, melting processes, and mechanical properties for nickel and iron aluminizes are presented. The current applications and commercial producers of nickel and iron aluminizes are given. A brief description of the future prospects of intermetallic-based alloys is also given.
Date: April 25, 1999
Creator: Sikka, V.K.
System: The UNT Digital Library
Three Dimensional, Integrated Characterization and Archival System for Remote Facility Contaminant Characterization (open access)

Three Dimensional, Integrated Characterization and Archival System for Remote Facility Contaminant Characterization

The largest problem facing the Department of Energy's Office of Environmental Management (EM) is the cleanup of the Cold War legacy nuclear production plants that were built and operated from the mid-forties through the late eighties. EM is now responsible for the remediation of no less than 353 projects at 53 sites across the country at, an estimated cost of $147 billion over the next 72 years. One of the keys to accomplishing a thorough cleanup of any site is a rigorous but quick contaminant characterization capability. If the contaminants present in a facility can be mapped accurately, the cleanup can proceed with surgical precision, using appropriate techniques for each contaminant type and location. The three dimensional, integrated characterization and archival system (3D-ICAS) was developed for the purpose of rapid, field level identification, mapping, and archiving of contaminant data. The system consists of three subsystems, an integrated work and operating station, a 3-D coherent laser radar, and a contaminant analysis unit. Target contaminants that can be identified include chemical (currently organic only), radiological, and base materials (asbestos). In operation, two steps are required. First, the remotely operable 3-D laser radar maps an area of interest in the spatial domain. Second, …
Date: April 25, 1999
Creator: Barry, R.E.; Gallman, P.; Jarvis, G. & Griffiths, P.
System: The UNT Digital Library
Manipulator Performance Evaluation Using Fitts' Taping Task (open access)

Manipulator Performance Evaluation Using Fitts' Taping Task

Metaphorically, a teleoperator with master controllers projects the user's arms and hands into a re- mote area, Therefore, human users interact with teleoperators at a more fundamental level than they do with most human-machine systems. Instead of inputting decisions about how the system should func- tion, teleoperator users input the movements they might make if they were truly in the remote area and the remote machine must recreate their trajectories and impedance. This intense human-machine inter- action requires displays and controls more carefully attuned to human motor capabilities than is neces- sary with most systems. It is important for teleoperated manipulators to be able to recreate human trajectories and impedance in real time. One method for assessing manipulator performance is to observe how well a system be- haves while a human user completes human dexterity tasks with it. Fitts' tapping task has been, used many times in the past for this purpose. This report describes such a performance assessment. The International Submarine Engineering (ISE) Autonomous/Teleoperated Operations Manipulator (ATOM) servomanipulator system was evalu- ated using a generic positioning accuracy task. The task is a simple one but has the merits of (1) pro- ducing a performance function estimate rather than a …
Date: April 25, 1999
Creator: Draper, J.V.; Jared, B.C. & Noakes, M.W.
System: The UNT Digital Library
Automated DNA Sequencing System (open access)

Automated DNA Sequencing System

Oak Ridge National Laboratory (ORNL) is developing a core DNA sequencing facility to support biological research endeavors at ORNL and to conduct basic sequencing automation research. This facility is novel because its development is based on existing standard biology laboratory equipment; thus, the development process is of interest to the many small laboratories trying to use automation to control costs and increase throughput. Before automation, biology Laboratory personnel purified DNA, completed cycle sequencing, and prepared 96-well sample plates with commercially available hardware designed specifically for each step in the process. Following purification and thermal cycling, an automated sequencing machine was used for the sequencing. A technician handled all movement of the 96-well sample plates between machines. To automate the process, ORNL is adding a CRS Robotics A- 465 arm, ABI 377 sequencing machine, automated centrifuge, automated refrigerator, and possibly an automated SpeedVac. The entire system will be integrated with one central controller that will direct each machine and the robot. The goal of this system is to completely automate the sequencing procedure from bacterial cell samples through ready-to-be-sequenced DNA and ultimately to completed sequence. The system will be flexible and will accommodate different chemistries than existing automated sequencing lines. The …
Date: April 25, 1999
Creator: Armstrong, G. A.; Ekkebus, C. P.; Hauser, L. J.; Kress, R. L. & Mural, R. J.
System: The UNT Digital Library
Lifetime Response of a Hi-Nicalon Fiber-Reinforced Melt-Infiltrated SiC Matrix Composites (open access)

Lifetime Response of a Hi-Nicalon Fiber-Reinforced Melt-Infiltrated SiC Matrix Composites

Lifetime studies in four-point flexure were performed on a Hi-Nicalon<sup>TM</sup> fiber-reinforced SiC matrix composite over a temperature range of 700 degrees to 1150 degrees C in air. The composite consisted of ~40 vol. % Hi-Nicalon<sup>TM</sup> fiber (8-harness weave) with a 0.5 Mu-m BN fiber coating and a melt-infiltration SiC matrix wand was tested with as-machined surfaces. Lifetime results indicated that the composite exhibited a stress-dependent lifetime at stress levels above an apparent fatigue limit, similar to the trend observed in CG-Nicalon<sup>TM</sup> fiber reinforced CVI SiC matrix composites. At less than or equal to 950 degrees C, the lifetimes of Hi-Nicalon/MI SiC composites decreased with increasing applied stress level and test temperature. However, the lifetimes were extended as test temperature increased from 950 degees to 1150 degrees C as a result of surface crack sealing due to glass formation by the oxidation of Mi SiC matrix. The lifetime governing processes were, in general, attributed to the progressive oxidation of BN fiber coating and formation of glassy phase, which formed a strong bond between fiber and matrix, resulting in embrittlement of the composite with time.
Date: April 25, 1999
Creator: Becher, P. F.; Lin, H. T. & Singh, M.
System: The UNT Digital Library
A MEMS-based miniature DNA analysis system (open access)

A MEMS-based miniature DNA analysis system

We detail the design and development of a miniature thermal cycling instrument for performing the polymerase chain reaction (PCR) that uses microfabricated, silicon-based reaction chambers. The MEMS-based, battery-operated instrument shows significant improvements over commercial thermal cycling instrumentation. Several different biological systems have been amplified and verified with the miniature PCR instrument including the Human Immunodeficiency Virus; both cloned and genomic DNA templates of {beta} globin; and the genetic disease, Cystic Fibrosis from human DNA. The miniaturization of a PCR thermal cycler is the initial module of a fully-integrated portable, low-power, rapid, and highly efficient bioanalytical instrument.
Date: April 25, 1995
Creator: Northrup, M.A.; Gonzalez, C. & Hadley, D.
System: The UNT Digital Library
Dual Arm Work Module Development and Appplications (open access)

Dual Arm Work Module Development and Appplications

The dual arm work module (DAWM) was developed at Oak Ridge National Laboratory (ORNL) by the Robotics Technology Development Program (RTDP) as a development test bed to study issues related to dual arm manipulation, including platform cotilguration, controls, automation, operations, and tooling. The original platform was based on two Schilling Titan II manipulators mounted to a 5-degree-of- freedom (DOF) base fabricated by RedZone Robotics, Inc. The 5-DOF articulation provided a center torso rotation, linear actuation to change the separation between the arms, and arm base rotation joints to provide "elbows up," elbows down," or "elbows out" orientation. A series of tests were conducted on operations, tooling, and task space scene analysis (TSSA)-driven robotics for overhead transporter- mounted and crane hook-deployed scenarios. A concept was developed for DAWM deployment from a large remote work vehicle, but the project was redirected to support dismantlement of the Chicago Pile #5 (CP-5) reactor at Argonne National Laboratory in fiscal year (FY) 1997. Support of CP-5 required a change in focus of the dual arm technology from that of a development test bed to a system focussed for a specific end user. ORNL teamed with the Idaho National Environmental ,Engineering Laboratory, Sandia National Laboratory, and …
Date: April 25, 1999
Creator: Noakes, M.W.
System: The UNT Digital Library
Damage Accumulation in MgAl{sub 2}O{sub 4} and Yttria-Stabilized ZrO{sub 2} by Xe-Ion Irradiation (open access)

Damage Accumulation in MgAl{sub 2}O{sub 4} and Yttria-Stabilized ZrO{sub 2} by Xe-Ion Irradiation

Magnesium-aluminate spinel (MAS) and yttria-stabilized zirconia (YSZ) are being considered for use as ceramic matrices in proliferation resistant fuels and radioactive storage systems, and may be used either as individual entities or as constituents in multicomponent ceramic systems. It is worthwhile, therefore, to compare radiation damage in these two potentially important materials when subjected to similar irradiation conditions, e.g., ion beam irradiation. To compare radiation damage properties of these two materials, single crystals of spinel and zirconia were irradiated with 340 keV Xe{sup ++} ions at 120 K, and subsequently investigated by Rutherford backscattering and ion channeling (RBS/C), and optical absorption spectroscopy. Results indicate that damage accumulation in both spinel and zirconia follow a three stage process: (1) very slow damage accumulation over a wide range of dose; (2) rapid changes in damage over a range of doses from about 0.25 to 25 displacements per atom (DPA); (3) slower damage accumulation at very high doses and possibly saturation. Optical absorption results indicate that F-centers form in Xe ion-irradiated spinel and that the concentration of these centers saturates at high dose. Absorption bands are also formed in both spinel and zirconia that are due to point defect complexes formed upon irradiation. …
Date: April 25, 1999
Creator: Afanasyev-Charkin, I.V.; Gritsyna, V.T.; Cooke, D.W.; Bennett, B.L. & Sickafus, K.E.
System: The UNT Digital Library
A Remotely Deployed Laser System for Viewing/Metrology (open access)

A Remotely Deployed Laser System for Viewing/Metrology

A metrology system is being developed for in-vessel inspection of present day experimental, and next generation fusion reactors. It requires accurate measuring capability to verify sub-millimeter alignment of plasma-facing components in the reactor vessel. A metrology system capable of achieving such accuracy for next generation reactors must be compatible with the vessel environment of high gamma radiation, high vacuum, elevated temperature, and magnetic field. This environment requires that the system must be remotely deployed. A coherent, frequency modulated laser radar system that is capable of correcting for environmental vibration meets these requirements. The metrologyhiewing system consists of a compact laser transceiver optics module which is linked through fiber optics to the laser source and imaging units, that are located outside of the harsh environment. The deployment mechanism configured for a next generation reactor was telescopic-mast positioning system. This paper identifies the requirements for the metrology/viewing system having precision ranging and surface mapping capability, and discusses the results of various environmental tests.
Date: April 25, 1999
Creator: Barry, Robert E.; Herndon, Joseph N.; Menon, Madhavan M. & Spampinato, Philip T.
System: The UNT Digital Library
Choppertron II (open access)

Choppertron II

We present experimental results of a version of the Choppertron microwave generator designed to work with the high emittance beam of the Advanced Test Accelerator (ATA). Simulations showed that a 800-A, 120 {pi} cm-mrad beam (typical of ATA), could produce 800 MW of rf (11.4 GHz) power using two 12-cell, traveling-wave output structures. Funding contraints prevented final tuning of the modulator system and limited the experiment to 530 MW in narrow pulses. Over 400 MW were extracted from a single output structure through fundamental waveguide. Beam breakup was successfully suppressed with >800 amperes transported through the extraction section.
Date: April 25, 1995
Creator: Houck, T.L.; Westenskow, G.A.; Haimson, J. & Mecklenburg, B.
System: The UNT Digital Library
Transport of a Partially-Neutralized Ion Beam in a Heavy-Ion Fusion Reactor Chamber (open access)

Transport of a Partially-Neutralized Ion Beam in a Heavy-Ion Fusion Reactor Chamber

In a heavy-ion driven, inertial confinement fusion power plant, a space-charge dominated beam of heavy ions must be transported through a reactor chamber and focused on a 2-3 mm spot at the target. The spot size at the target is determined by the beam emittance and space charge, plus chromatic aberrations in the focusing lens system and errors in aiming the beam. The gain of the ICF capsule depends on the focal spot size. We are investigating low density, nearly-ballistic transport using an electromagnetic, r-z particle-in-cell code. Even at low density (n {approx} 5 {times} 10{sup 13} cm{sup {minus}3}), beam stripping may be important. To offset the effects of stripping and reduce the space charge, the beam is partially charge neutralized via a pre-formed plasma near the chamber entrance. Additional electrons for charge neutralization come from ionization of the background gas by the beam. Simulations have shown that stripping can greatly increase the spot size; however, partial neutralization can offset most of this increase.
Date: April 25, 1995
Creator: Callahan, D. A. & Langdon, A. B.
System: The UNT Digital Library
Scarab III Remote Vehicle Deployment for Waste Retrieval and Tank Inspection (open access)

Scarab III Remote Vehicle Deployment for Waste Retrieval and Tank Inspection

The Robotics Technology Development Program now known as the Robotics Crosscut Program, funded the development and deployment of a small remotely operated vehicle for inspection and cleanout of small horizontal waste storage tanks that have limited access. Besides the advantage of access through tank risers as small as 18-in. diameter, the small robotic system is also significantly less expensive to procure and to operate than larger remotely operated vehicle (ROV) systems. The vehicle specified to support this activity was the ROV Technologies, Inc., Scarab. The Scarab is a tracked vehicle with an independently actuated front and rear ''toe'' degree-of-freedom which allows the stand-off and angle of the vehicle platform with respect to the floor to be changed. The Scarab is a flexible remote tool that can be used for a variety of tasks with its primary uses targeted for inspection and small scale waste retrieval. The vehicle and any necessary process equipment are mounted in a deployment and containment enclosure to simplify deployment and movement of the system from tank to tank. This paper outlines the technical issues related to the Scarab vehicle and its deployment for use in tank inspection and waste retrieval operation
Date: April 25, 1999
Creator: Burks, B.L.; Falter, D.D.; Noakes, M. & Vesco, D.
System: The UNT Digital Library
Sintering Studies of Ga-Doped CeO{sub 2} (Ga-Doped PuO{sub 2} Surrogate) for Mixed Oxide Nuclear Fuel (open access)

Sintering Studies of Ga-Doped CeO{sub 2} (Ga-Doped PuO{sub 2} Surrogate) for Mixed Oxide Nuclear Fuel

Sintering studies of CeO{sub 2} and CeO{sub 2} + 2 wt. % Ga{sub 2}O{sub 3} were completed. Firing temperatures studied were 1250-1650 C with 2 to 4 hour firing soak times in air. Powders fabricated by three methods (as-received, attrition-mill and nitrite-derived) were studied. Attrition-milled CeO{sub 2} improved densities as compared with as-received CeO{sub 2}. Attrition-milled CeO{sub 2} with 2 wt.% Ga{sub 2}O{sub 3} showed decreased densities with increasing temperatures. As-received CeO{sub 2} with 2 wt.% Ga{sub 2}O{sub 3} showed a opposite trend, increasing in density with increased firing temperature. Two pellet preparation methods were studied, a one-step-press method and a two-step-press method. The two-step-press method showed greater densities at lower firing temperatures and times as compared with the one-step-press method, however for CeO{sub 2} + 2 wt.% Ga{sub 2}O{sub 3}, the two methods gave equivalent results at 1650 C, 6 hr. firing conditions.
Date: April 25, 1999
Creator: Haertling, C.; Huling, J. & Park, Y. S.
System: The UNT Digital Library