The CDF TESTCLK module - Providing system level clocking and triggering for Run 2 prototyping crates (open access)

The CDF TESTCLK module - Providing system level clocking and triggering for Run 2 prototyping crates

The TESTCLK module was specifically designed for use in prototyping crates for the Colliding Detector Facility (CDF) Run 2 Experiment at Fermi National Accelerator Laboratory. The TESTCLK Module allows the user to supply system clocks and trigger signals to stand-alone crates. This module has allowed designers of the CDF Run 2 electronics to thoroughly test their modules, despite the lack of a DAQ system supplied clock and trigger interface. This paper will explore the features that were found important to incorporate into the TESTCLK, and describe how they were implemented. The paper will also describe how the TESTCLK module has been used to support the initial implementation of the DAQ system at CDF. This has allowed data taking and testing of CDF Electronic modules before production clock and trigger modules became available.
Date: November 5, 1999
Creator: Stuermer, Theresa Shaw and Walter
Object Type: Article
System: The UNT Digital Library
Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California (open access)

Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California

Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic …
Date: October 5, 1999
Creator: Daniels, J I; Bogen, K T & Hall, L C
Object Type: Report
System: The UNT Digital Library
Establishment of Harrop, High-Temperature Viscometer (open access)

Establishment of Harrop, High-Temperature Viscometer

This report explains how the Harrop, High-Temperature Viscometer was installed, calibrated, and operated. This report includes assembly and alignment of the furnace, viscometer, and spindle, and explains the operation of the Brookfield Viscometer, the Harrop furnace, and the UDC furnace controller. Calibration data and the development of the spindle constant from NIST standard reference glasses is presented. A simple operational procedure is included.
Date: November 5, 1999
Creator: Schumacher, R. F.
Object Type: Report
System: The UNT Digital Library
Dynamics of the Inflationary Era (open access)

Dynamics of the Inflationary Era

There is very strong circumstantial evidence that there was an inflationary epoch very early in the history of the universe. In this lecture the author describes how we might be able to piece together some understanding of the dynamics during and immediately after the inflationary epoch.
Date: November 5, 1999
Creator: Kolb, Edward W.
Object Type: Article
System: The UNT Digital Library
Single top production and top properties at the Tevatron (open access)

Single top production and top properties at the Tevatron

We summarize recent measurements made at the Tevatron Collider using top event candidates. Cross section and mass measurements are discussed in a separate contribution to these Proceedings. Here we report on studies of the top P<sub>T</sub> distribution in t{anti t} production and studies of single top production. Properties of top decays examined are: BF(t {yields} Wb)/BF(t {yields} Wq), helicity amplitudes of W's from top decays and correlations of t{anti t} decay products. Searches for new physics in rare top decays and a search for a state X {yields} t{anti t} are also reported.
Date: November 5, 1999
Creator: Barbaro-Galtieri, Angela
Object Type: Article
System: The UNT Digital Library
Observations of Non-Close-Packed Arrangements in Multilayers of Passivated Gold Clusters (open access)

Observations of Non-Close-Packed Arrangements in Multilayers of Passivated Gold Clusters

The stacking of second and third layers of supercrystals of self-assembled passivated gold nanoparticles has been investigated using transmission electron microscopy. We report for the first time nanoparticles occupying the twofold saddle site in the third layer.
Date: October 5, 1999
Creator: AINDOW, M.; Brown, P.; Kiely, C. J.; Wellner, A. & Wilcoxon, Jess P.
Object Type: Article
System: The UNT Digital Library
Signals from Microwave Unstable Beams in the SLC Damping Rings (open access)

Signals from Microwave Unstable Beams in the SLC Damping Rings

The longitudinal microwave instability is present in the SLC damping rings during routine operations. Experimental studies of the instability at nominal conditions have been reported previously. To complement those studies and better understand the properties of the instability a series of dedicated experiments were performed under a broad range of operating parameters. These experiments included spectral measurements of BPM signals as well as time domain diagnostics using a custom detecting circuit. This paper describes the techniques, the results and discusses possible interpretations of these measurements.
Date: April 5, 1999
Creator: Podobedev, Boris
Object Type: Report
System: The UNT Digital Library
The quandry of benchmarking broadcasts (open access)

The quandry of benchmarking broadcasts

A message passing library's implementation of broadcast communication can significantly affect the performance of applications built with that library. In order to choose between similar implementations or to evaluate available libraries, accurate measurements of broadcast performance are required. As we demonstrate, existing methods for measuring broadcast performance are either inaccurate or inadequate. Fortunately, we have designed an accurate method for measuring broadcast performance. Measuring broadcast performance is not simple. Simply sending one broadcast after another allows them to proceed through the network concurrently, thus resulting in accurate per broadcast timings. Existing methods either fail to eliminate this pipelining effect or eliminate it by introducing overheads that are as difficult to measure as the performance of the broadcast itself. Our method introduces a measurable overhead to eliminate the pipelining effect.
Date: February 5, 1999
Creator: Karonis, N T & Supinski, B R
Object Type: Article
System: The UNT Digital Library
Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools (open access)

Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools

This work combines focused ion beam sputtering and ultra-precision machining as a first step in fabricating microstructure in metals and alloys. Specifically, {approx}25{micro}m diameter micro-end mills are made from cobalt M42 high-speed steel and C2 micrograin tungsten carbide tool blanks by ion beam sputtering. A 20 keV focused gallium beam defines tool cutting edges having radii of curvature &lt; 0.1{micro}m. Micro-end mills having 2, 4 and 5 cutting edges successfully machine small trenches in 6061-T4 aluminum, brass, 4340 steel and polymethyl methacrylate. Machined trench widths are approximately equal to the tool diameters and surface roughnesses (rms) are {approx}150 nm or less. Microtools are robust and operate for more than 6 hours without fracture. Results from ultra-precision machining aluminum at feed rates as high as 50 mm/minute are included.
Date: November 5, 1999
Creator: ADAMS,DAVID P.; VASILE,M.J.; BENAVIDES,GILBERT L. & CAMPBELL,ANN N.
Object Type: Article
System: The UNT Digital Library
FY 1999 Annual Self-Evaluation Report of the Pacific Northwest National Laboratory (open access)

FY 1999 Annual Self-Evaluation Report of the Pacific Northwest National Laboratory

This is a report of the Pacific Northwest National Laboratory's (Pacific Northwest's) FY1999 Annual Self-Evaluation Report. This report summarizes our progress toward accomplishment of the critical outcomes, objectives, and performance indicators as delineated in the FY1999 Performance Evaluation & Fee Agreement. It also summarizes our analysis of the results of Pacific Northwest's Division and Directorate annual self-assessments, and the implementation of our key operational improvement initiatives. Together, these provide an indication of how well we have used our Integrated Assessment processes to identify and plan improvements for FY2000. As you review the report you will find areas of significantly positive progress; you will also note areas where I believe the Laboratory could make improvements. Overall, however, I believe you will be quite pleased to note that we have maintained, or exceeded, the high standards of performance we have set for the Laboratory.
Date: November 5, 1999
Creator: LaBarge, Randy R.
Object Type: Report
System: The UNT Digital Library
Renewable Energy for Sustainable Rural Village Power (open access)

Renewable Energy for Sustainable Rural Village Power

It is estimated that two billion people live without electricity and its services worldwide. In addition, there is a sizeable number of rural villages that have limited electrical service, with either part-day operation by diesel generator or partial electrification. For many villages connected to the grid, power is often sporadically available and of poor quality. The US National Renewable Energy Laboratory (NREL) in Golden, Colorado, has initiated a program that involves hybrid systems, to address these potential electricity opportunities in rural villages through the application of renewable energy technologies.1 The objective of this program is to develop and implement applications that demonstrate the technical performance, economic competitiveness, operational viability, and environmental benefits of renewable rural electric solutions, compared to the conventional options of line extension and isolated diesel mini-grids. Hybrid systems are multi-disciplinary, multi-technology, multi-application programs composed of six activities, including village applications development, computer model development, systems analysis, pilot project development, technical assistance, and Internet-based village power project data base. While the current program emphasizes wind, photovoltaics (PV), and their hybrids with diesel generator, micro-hydro and micro-biomass technologies may be integrated in the future. Thirteen countries are actively engaged in hybrid systems for rural and remote applications and another …
Date: August 5, 1999
Creator: Touryan, J. O. V. & Touryan, K. J.
Object Type: Article
System: The UNT Digital Library
The design and PCB layout of the CDF Run 2 calorimetry readout module (open access)

The design and PCB layout of the CDF Run 2 calorimetry readout module

The CDF Calorimetry Readout module, called the ADMEM, has been designed to contain both the analog circuitry which digitizes the phototube charge pulses, and the digital logic which supports the readout of the results through the CDF Run 2 DAQ system. The ADMEM module is a 9Ux400mm VMEbus module, which is housed in a CDF VMEbus VIPA crate. The ADMEM must support near deadtimeless operation, with data being digitized and stored for possible readout every 132ns or 7.6 Mhz. This paper will discuss the implementation of the analog and digital portions of the ADMEM module, and how the board was laid out to avoid the coupling of digital noise into the analog circuitry.
Date: November 5, 1999
Creator: al., Theresa Shaw et
Object Type: Article
System: The UNT Digital Library
Observation of the decay K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} (open access)

Observation of the decay K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}

We have observed 1 event consistent with the signature expected of the rare decay of a positive kaon to a positive pion and a neutrino anti-neutrino pair. In the examined momentum region of 211 to 230 MeV/c in the center of mass of the kaon we estimated the backgrounds to be about 0.08 {+-} 0.03 events. From this observation we estimate the branching ratio to be 4.2{sub {minus}3.5}{sup +9.7} x 10{sup {minus}10}. In this presentation I will explain the experiment, and the analysis techniques. I will also discuss the expected improvements in the near future from the analysis of new data sets.
Date: January 5, 1999
Creator: Diwan, M. B.
Object Type: Article
System: The UNT Digital Library
Evaluation of Optimal Distribution of Wind Power Facilities in Iowa for 2015 (open access)

Evaluation of Optimal Distribution of Wind Power Facilities in Iowa for 2015

By the end of June 1999, about 250 megawatts of wind generation will have been dedicated in the state of Iowa. This represents the beginning of what is likely to be significant wind capacity development during the next 20 years in the state, as a result of possible public and governmental mandates and consumers' desire for sustainable sources of energy. As the utility industry in the United States moves towards a new structure, renewable energy sources continue to be an important part of new resource development. In this paper, we consider the predicted trends in load growth in Iowa. After accounting for the retirement of nuclear and older fossil fuel facilities over the next 15 years, we estimate Iowa's potential renewable generating capacity through the year 2015 and anticipate the contribution of wind energy to Iowa's portfolio. The Iowa Wind Energy Institute (IWEI) has been monitoring the wind resource in Iowa since June 1994 to obtain wind speed averages at 10, 33 and 50 meters above ground at fourteen geographically dispersed potential wind farm sites. Winds in the Midwest are primarily generated by fronts moving through the region. The Northwest Buffalo Ridge area of Iowa typically has wind speed averages …
Date: August 5, 1999
Creator: Factor, T. (Iowa Wind Energy Institute) & Milligan, M. (National Renewable Energy Laboratory)
Object Type: Article
System: The UNT Digital Library
Hydrodynamics of Gas-Liquid Counterflow Through Corrugated Parallel Plates (open access)

Hydrodynamics of Gas-Liquid Counterflow Through Corrugated Parallel Plates

Structured packings utilized in today's distillation packed towers consist of stacked units of many vertically oriented parallel corrugated plates. The V-shaped corrugations are oriented at a fixed angle with respect to the vertical direction, and the corrugation angle in adjacent plates are oriented in reverse direction. Points of contact, at the crests of the corrugations, between adjacent plates, form an unconsolidated porous medium with known topology. Modern structured packings have been gaining acceptance in several separation processes, particularly distillation where gas/vapor and liquid flow countercurrently through the packing. In addition, structured packings have been credited with relatively low pressure drop, high efficiency, low holdup, and higher capacity; the packing also can be made corrosion resistive.
Date: November 5, 1999
Creator: de Almeida, V.F.
Object Type: Article
System: The UNT Digital Library
Alignment tolerances of IR quadrupoles in the LHC (open access)

Alignment tolerances of IR quadrupoles in the LHC

Luminosity in the LHC will depend critically on the alignment of the triplet quadrupoles. These quadrupoles are closest to the interaction points (IPs), have large gradients and the {beta} functions have their largest values within these quadrupoles. Within a triplet, the cold masses of the Q1 and Q3 quadrupoles will be housed in separate cryostats while Q2a and Q2b will be placed in a single cryostat. The absolute alignments of Q1, Q3 and the Q2a/Q2b pair with respect to the desired axes will be determined during installation. The relative alignment of Q2a and Q2b however will be fixed once they are placed in their common cryostat at Fermilab. In this note, we examine the required relative alignment tolerances of Q2a and Q2b. An early study of some alignment tolerances was done by Weisz [1].
Date: November 5, 1999
Creator: Sen, Tanaji
Object Type: Article
System: The UNT Digital Library
Evaluation of Potential Melt-Dilute/Neutron Absorber Systems for DOE SNF Disposal System (open access)

Evaluation of Potential Melt-Dilute/Neutron Absorber Systems for DOE SNF Disposal System

Approximately 50 metric tonnes heavy metal of aluminum-base spent nuclear fuel (Al-SNF) or 30,000 assemblies are being consolidated at the Savannah River Site. The melt-dilute (MD) technology option is being developed to allow ultimate disposal of these fuels in the Monitored Geologic Repository (MGR). Neutron absorbing materials are needed to maintain k{sub eff} less than 0.95 in desired packaging configurations. The aggressive chemical environment in the MGR is expected to lead to the reconfiguration of the contents of the codisposal waste package following waste package failure. This reconfiguration has the potential for increasing the reactivity of the waste package. The reconfiguration and redistribution of materials within the waste package are being investigated in an analytical and experimental program to support the criticality analysis. Further, the incorporation of neutron absorbing materials that will be integral to the MD SNF form is being investigated.
Date: November 5, 1999
Creator: Vinson, D.
Object Type: Article
System: The UNT Digital Library
SECOND GENERATION PFBC SYSTEMS R AND D - PHASE 2 AND 3 (open access)

SECOND GENERATION PFBC SYSTEMS R AND D - PHASE 2 AND 3

When DOE funds were exhausted in March 1995, all Phase 2 activities were placed on hold. In February 1996 a detailed cost estimate was submitted to the DOE for completing the two remaining Phase 2 Multi Annular Swirl Burner (MASB) topping combustor test campaigns; in August 1996 release was received from FETC to proceed with the two campaigns to: (1) test the MASB at proposed demonstration plant full to minimum load operating conditions; (2) identify the lower oxygen limit of the MASB; (3) demonstrate natural gas to carbonizer fuel gas switching; and (4) demonstrate operation with ''low temperature'' compressor discharge air rather than high temperature ({approx}1600 F) vitiated air.
Date: August 5, 1999
Creator: Robertson, A.
Object Type: Report
System: The UNT Digital Library
An updated measurement of sin (2{Beta}) at CDF (open access)

An updated measurement of sin (2{Beta}) at CDF

We report an updated direct measurement of the Standard Model CP violation parameter sin(2{beta}) using the CDF Detector at Fermilab. We use the entire Run-I data sample of 110 pb{sup -1} of proton-antiproton collisions at {radical}s = 1.8 TeV. In this analysis, we have combined three tagging methods: a same-side tag, a soft-lepton tag, and a jet-charge tag, and also added events that have less precise lifetime information because they are not fully contained within the acceptance of the SVX. The signal sample consists of {approx} 400 B {yields} J/{psi} K{sub S}{sup 0} events. A maximum likelihood fitting method is used to measure sin(2{beta}) = 0.79{sub -0.44}{sup +0.41} (stat.+syst.). We calculate a 93% Feldman-Cousins confidence interval of 0 &lt; sin(2{beta}) &lt; 1. This measurement is the best direct indication for CP violation in the neutral B meson sector to date. The sin(2{beta}) value is consistent with the Standard Model prediction of large CP symmetry violation in the b quark system.
Date: November 5, 1999
Creator: Bedeschi, Franco
Object Type: Article
System: The UNT Digital Library
Reactor Materials Program - Baseline Material Property Handbook - Mechanical Properties of 1950's Vintage Stainless Steel Weldment Components, Task Number 89-23-A-1 (open access)

Reactor Materials Program - Baseline Material Property Handbook - Mechanical Properties of 1950's Vintage Stainless Steel Weldment Components, Task Number 89-23-A-1

The Process Water System (primary coolant) piping of the nuclear production reactors constructed in the 1950''s at Savannah River Site is comprised primarily of Type 304 stainless steel with Type 308 stainless steel weld filler. A program to measure the mechanical properties of archival PWS piping and weld materials (having approximately six years of service at temperatures between 25 and 100 degrees C) has been completed. The results from the mechanical testing has been synthesized to provide a mechanical properties database for structural analyses of the SRS piping.
Date: November 5, 1999
Creator: Stoner, K. J.
Object Type: Report
System: The UNT Digital Library
Protocols and standard crate configuration for a typical CDF Run 2 readout crate (open access)

Protocols and standard crate configuration for a typical CDF Run 2 readout crate

This paper describes a standard for the readout and the trigger interface of a VMEbus based crate to be used by the front-end and trigger electronics of the CDF Run 2 experiment. Hereafter, this crate will be referred to as the CDF Readout Crate. The goal is to standardize the implementation of functions that are common among all systems (i.e. power distribution, timing signals, DAQ functions) while allowing some flexibility with other functions (e.g. cooling, rear transition modules, J3 backplanes, etc.). This allows designers of cards that satisfy this standard to have access to a common well defined crate system with interfaces to the trigger and DAQ system, allowing them to concentrate their efforts on the functions they need. This paper lists the mechanical specifications, readout scheme, backplane and signal distribution specifications of the CDF Readout Crate. The paper will also go into some detail on the TRigger And Clock + Event Readout (TRACER) module, a common CDF crate module which provides the crate interface to the system clock and the trigger system.
Date: November 5, 1999
Creator: al., Theresa Shaw et
Object Type: Article
System: The UNT Digital Library
Borel Summation and Momentum-Plane Analyticity in Perturbative QCD (open access)

Borel Summation and Momentum-Plane Analyticity in Perturbative QCD

We derive a compact expression for the Borel sum of a QCD amplitude in terms of the inverse Mellin transform of the corresponding Borel function. The result allows us to investigate the momentum-plane analyticity properties of the Borel-summed Green functions in perturbative QCD. An interesting connection between the asymptotic behavior of the Borel transform and the Landau singularities in the momentum plane is established. We consider for illustration the polarization function of massless quarks and the resummation of one-loop renormalon chains in the large-{beta}{sub 0} limit, but our conclusions have a more general validity.
Date: February 5, 1999
Creator: Neubert, Matthias
Object Type: Report
System: The UNT Digital Library
Effects of Beamtube Roughness on X-Ray FEL Performance (open access)

Effects of Beamtube Roughness on X-Ray FEL Performance

In an X-Ray FEL like the Linear Coherent Light Source (LCLS) being designed at SLAC, electron bunches about 70 {micro}m FWHM long are sent into a beam tube only 5 mm in internal diameter and more than 100 m in length. Due to the surface roughness of the beam tube, wakefields can be generated that catch up to the bunch and interact with it, causing energy spread and emittance growth. The strength of this effect depends on the details of the roughness of the surface. We present here a study in which the roughness of the beam tube was measured, and the longitudinal impedance of the tube was calculated. Our result shows that commercially available beam tube can be made smooth enough so the resulting wakefield effects are within the tolerance determined by the requirement that the induced relative energy spread of the beam be less then 5 x 10{sup {minus}4}.
Date: April 5, 1999
Creator: Stupakov, Gennady
Object Type: Report
System: The UNT Digital Library
Ion Beam Sputter Fabrication of Micro-Grooving and Micro-Threading Tools (open access)

Ion Beam Sputter Fabrication of Micro-Grooving and Micro-Threading Tools

This paper presents techniques for fabricating microscopic, nonplanar features in a variety of materials. Micro-grooving and micro-threading tools having cutting dimensions of 10-30{micro}m are made by focused ion beam sputtering and used in ultra-precision machining. Tool fabrication involves directing a 20 keV gallium beam at polished cylindrical punches made of cobalt M42 high-speed steel or C2 tungsten carbide. This creates cutting edges having radii of curvature less than 0.4 {micro}m, and rake features similar to conventional lathe tools. Clearance for minimizing frictional drag of a tool results from the sputter yield dependence on ion herd target incidence angle. Numerically controlled, ultra-precision machining with micro-grooving tools results in a close matching between tool width and feature size. Microtools controllably machine 13 {micro}m wide, 4 {micro}m deep, helical grooves in polymethyl methacrylate and 6061-T6 Al cylindrical substrates. Micro-grooving tools also fabricate sinusoidal waveform features in polished metal substrates.
Date: November 5, 1999
Creator: Adams,David P.; Vasile,M. J. & Krishnan,A. S. M.
Object Type: Article
System: The UNT Digital Library