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CDFVME -- Software framework for testing VME boards (open access)

CDFVME -- Software framework for testing VME boards

New VME based boards are being produced for the Run II of the Collider Detector at Fermilab (CDF). These boards are being developed and tested at both Fermilab and offsite institutions. A software framework called CDFVME has been developed in which DAQ code can be easily written to control such boards in a test stand. The framework has been used to perform diagnostics at single board, multi-board, and multi-crate levels. This software framework runs on Unix, Linux and Windows NT platforms with a Java GUI communicating via LAN to multiple intelligent front end VME crates. All distributed processes are managed by a custom CORBA based software. The system has been ported to Motorola 68K and PPC front end processors running the VxWorks real-time kernel [1].
Date: July 22, 1999
Creator: Gay, C.
System: The UNT Digital Library
High Accuracy, High Energy He-Erd Analysis of H,C, and T (open access)

High Accuracy, High Energy He-Erd Analysis of H,C, and T

A new analysis technique using high-energy helium ions for the simultaneous elastic recoil detection of all three hydrogen isotopes in metal hydride systems extending to depths of several {micro}m's is presented. Analysis shows that it is possible to separate each hydrogen isotope in a heavy matrix such as erbium to depths of 5 {micro}m using incident 11.48MeV {sup 4}He{sup 2} ions with a detection system composed of a range foil and {Delta}E-E telescope detector. Newly measured cross sections for the elastic recoil scattering of {sup 4}He{sup 2} ions from protons and deuterons are presented in the energy range 10 to 11.75 MeV for the laboratory recoil angle of 30{degree}.
Date: July 22, 1999
Creator: Browning, James F.; Langley, Robert A.; Doyle, Barney L.; Banks, James C. & Wampler, William R.
System: The UNT Digital Library
Equation-of-State Measurements with Z-Pinch Sources (open access)

Equation-of-State Measurements with Z-Pinch Sources

Validation of material models in a variety of scientific and technological applications requires accurate data regarding the high-pressure thermodynamic and mechanical properties. Traditional laboratory techniques for striking these measurements involve light gas guns to generate the required thermodynamic states, and the use of high-resolution time-resolved diagnostics to measure the desired material properties. EOS and constitutive material properties of importance to modeling needs include high-pressure Hugoniot curves and off-Hugoniot properties, such as. material strength and isentropic compression and decompression [1]. Conventional light gas guns are limited to impact pressures of about 7 Mbar in high-impedance materials. Pulsed radiation sources, such as high-intensity lasers, and pulsed power techniques significantly extend the accessible pressures and are becoming accepted methods for meeting the needs of material models in regimes inaccessible by gas guns. A present limitation of these new approaches is that samples must necessarily be small, typically a few tens of microns in thickness, which severely limits the accuracy of EOS measurements that can be made and also the ability to perform a variety of off-Hugoniot measurements. However, recent advances in z-pinch techniques for high-pressure material response studies provide potential opportunities for achieving accuracies comparable with gas guns because of the significantly larger …
Date: July 22, 1999
Creator: Asay, J. R.; Hall, C.; Bailey, J. E.; Knudson, M. D.; Holland, K. G.; Hanson, D. L. et al.
System: The UNT Digital Library
Ion Beam Induced Charge Collection (IBICC) Studies of Cadmium Zinc Telluride (CZT) Radiation Detectors (open access)

Ion Beam Induced Charge Collection (IBICC) Studies of Cadmium Zinc Telluride (CZT) Radiation Detectors

Cadmium Zinc Telluride is an emerging material for room temperature radiation detectors. In order to optimize the performance of these detectors, it is important to determine how the electronic properties of CZT are related to the presence of impurities and defects that are introduced during the crystal growth and detector fabrication. At the Sandia microbeam facility IBICC and Time Resolved IBICC (TRIBICC) were used to image electronic properties of various CZT detectors. Two-dimensional areal maps of charge collection efficiency were deduced from the measurements. In order to determine radiation damage to the detectors, we measured the deterioration of the IBICC signal as the function of dose. A model to explain quantitatively the pattern observed in the charge collection efficiency maps of the damaged detectors has been developed and will be discussed in the paper.
Date: July 22, 1999
Creator: Doyle, B.L.; Vizkelethy, G. & Walsh, D.S.
System: The UNT Digital Library
Use of the Known-M Method for NDA of Plutonium Scrap (open access)

Use of the Known-M Method for NDA of Plutonium Scrap

'Plutonium scrap from another Department of Energy site is to be converted at Savannah River Site (SRS) to a form for permanent storage. For accountability and criticality safety, the material must be measured at SRS, and handling restrictions require assay in 9975 shipping drums. A Multiplicity Neutron Counter is available to perform the measurements, but requires about 12 hours per assay, too long to support the measurement schedule. The assay time has been reduced to 2 hours by use of the Known-M method, the first known routine application of Known-M. The approach involves expression of the multiplication in terms of the effective <sup>239</sup>Pu mass and a quadratic polynomial. Because only a few measured values of multiplication were available, values from Monte Carlo neutron transport calculations (using code MCNP) were used. Because the scrap cans have variable fill heights and fill height affects multiplication, an algorithm to correct the effective <sup>239</sup>Pu mass values for that effect was developed. Testing of the Known-M calibration with limited data suggests a 2-sigma uncertainty of about 5 percent. Drums can contain one or two individual scrap cans, and an algorithm for measuring the combined plutonium content in two cans was developed. The Known-M assay calculations …
Date: July 22, 1999
Creator: Thompson, R.S.
System: The UNT Digital Library
Parallel-Plate Electrostatic Dual Mass Oscillator (open access)

Parallel-Plate Electrostatic Dual Mass Oscillator

A surface-micromachined two-degree-of-freedom system that was driven by parallel-plate actuation at antiresonance was demonstrated. The system consisted of an absorbing mass connected by folded springs to a drive mass. The system demonstrated substantial motion amplification at antiresonance. The absorber mass amplitudes were 0.8-0.85 pm at atmospheric pressure while the drive mass amplitudes were below 0.1 pm. Larger absorber mass amplitudes were not possible because of spring softening in the drive mass springs. Simple theory of the dual-mass oscillator has indicated that the absorber mass may be insensitive to limited variations in strain and damping. This needs experimental verification. Resonant and antiresonant frequencies were measured and compared to the designed values. Resonant frequency measurements were difficult to compare to the design calculations because of time-varying spring softening terms that were caused by the drive configuration. Antiresonant frequency measurements were close to the design value of 5.1 kHz. The antiresonant frequency was not dependent on spring softening. The measured absorber mass displacement at antiresonance was compared to computer simulated results. The measured value was significantly greater, possibly due to neglecting fringe fields in the force expression used in the simulation.
Date: July 22, 1999
Creator: Allen, James J.; Dyck, Christopher W. & Huber, Robert J.
System: The UNT Digital Library
Radiation monitoring for vertex detectors at the Tevatron (open access)

Radiation monitoring for vertex detectors at the Tevatron

I present an overview of radiation monitoring for vertex detectors and the abort system for the Fermilab Tevatron. Details on the detectors, inputs, and measurements for the Run 1 time period are provided. Plans for the monitoring during Run 2 are discussed. The measurements imply an approximately even mix of radiation from beam-beam collisions and beam losses.
Date: July 22, 1999
Creator: Derwent, P.F.
System: The UNT Digital Library
Solid Freeform Fabrication Using the Wirefeed Process (open access)

Solid Freeform Fabrication Using the Wirefeed Process

Direct metal deposition technologies produce complex, near net shape components from CAD solid models. Most of these techniques fabricate a component by melting powder in a laser weld pool, rastering this weld bead to form a layer, and additively constructing subsequent layers. This talk describes a new direct metal deposition process, known as WireFeed, whereby a small diameter wire is used instead of powder as the feed material to fabricate components. Currently, parts are being fabricated from stainless steel. Microscopy studies show the WireFeed parts to be fully dense with fine microstructural features. Initial mechanical tests show stainless steel parts to have good strength values with retained ductility.
Date: July 22, 1999
Creator: Buchheit, T. E.; Crenshaw, T. B.; Ensz, M. T.; Greene, D. L.; Griffith, M. L.; Harwell, L. D. et al.
System: The UNT Digital Library
Design of Experiments to Estimate Temperature Dependent Thermal Properties (open access)

Design of Experiments to Estimate Temperature Dependent Thermal Properties

Experimental conditions are studied to optimize transient experiments for estimating temperature dependent thermal conductivity and volumetric heat capacity. Thermal properties are assumed to vary linearly with temperature; a total of four parameters describe linearly varying thermal conductivity and volumetric heat capacity. A numerical model of experimental configurations is studied to determine the optimum conditions to conduct the experiment. The criterion D-optimality is used to study the sensor locations, heating duration and magnitude, and experiment duration for finite and semi-infinite configurations. Results indicate that D-optimality is an order of magnitude larger for the finite configuration and hence will provide estimates with a smaller confidence region.
Date: July 22, 1999
Creator: Blackwell, B. F. & Dowding, K. J.
System: The UNT Digital Library
Intermediate Strain-Rate Loading - Techniques and Applications (open access)

Intermediate Strain-Rate Loading - Techniques and Applications

A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.
Date: July 22, 1999
Creator: Chhabildas, L. C.; Reinhart, W. D. & Holland, K. G.
System: The UNT Digital Library
Thomson Scattering From Inertial Confinement Fusion Targets (open access)

Thomson Scattering From Inertial Confinement Fusion Targets

We have applied ultraviolet Thomson scattering to accurately measure the electron and ion temperature in high-density gas-filled hohlraums at the Nova laser facility. The implementation of a short-wavelength probe laser that operates at 263 nm (4{omega}) has allowed us for the first time to investigate scalings to high gas fill densities and to characterize the hohlraum conditions of the low-Z gas plasma. as well as of the high-Z wall plasma. These measurements have provided us with a unique data set that we use to make critical comparisons with radiation-hydrodynamic modeling using the code LASNEX. This code is presently being applied to design fusion targets for the National Ignition Facility. The Thomson scattering experiments show the existence of electron temperature gradients in the gas plasma that are well modeled when including a self-consistent calculation of magnetic fields. The fields are of relatively small strength not affecting the Thomson scattering spectra directly but limiting the electron thermal transport in the gas resulting into temperature gradients consistent with the experimental observations. In addition, the ion temperature data show that the stagnation time of the gas plasma on the hohlraum axis, which is driven by the radial inward flowing plasma, is sensitive to the …
Date: July 22, 1999
Creator: Baldis, H. A.; Estabrook, K. G.; Glenzer, S. H. & Suter, L. J.
System: The UNT Digital Library
Data acquisition systems at Fermilab (open access)

Data acquisition systems at Fermilab

Experiments at Fermilab require an ongoing program of development for high speed, distributed data acquisition systems. The physics program at the lab has recently started the operation of a Fixed Target run in which experiments are running the DART[1] data acquisition system. The CDF and DØ experiments are preparing for the start of the next Collider run in mid 2000. Each will read out on the order of 1 million detector channels. In parallel, future experiments such as BTeV R&D and Minos have already started prototype and test beam work. BTeV in particular has challenging data acquisition system requirements with an input rate of 1500 Gbytes/sec into Level 1 buffers and a logging rate of 200 Mbytes/sec. This paper will present a general overview of these data acquisition systems on three fronts � those currently in use, those to be deployed for the Collider Run in 2000, and those proposed for future experiments. It will primarily focus on the CDF and DØ architectures and tools.
Date: July 22, 1999
Creator: Votava, M.
System: The UNT Digital Library
Time Lens Based Single-Shot Ultrafast Waveform Recording: From High Repetition Rate to High Dynamic Range (open access)

Time Lens Based Single-Shot Ultrafast Waveform Recording: From High Repetition Rate to High Dynamic Range

None
Date: July 22, 2011
Creator: Bennett, C. V.; Hernandez, V. J.; Moran, B. D.; Lowry, M. E.; Vernon, S. P.; Steele, P. T. et al.
System: The UNT Digital Library
A HIGH REPETITION PLASMA MIRROR FOR STAGED ELECTRON ACCELERATION (open access)

A HIGH REPETITION PLASMA MIRROR FOR STAGED ELECTRON ACCELERATION

In order to build a compact, staged laser plasma accelerator the in-coupling of the laser beam to the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage.
Date: July 22, 2011
Creator: Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei et al.
System: The UNT Digital Library
Demonstration of a Plasma Mirror Based on a Laminar Flow Water Film (open access)

Demonstration of a Plasma Mirror Based on a Laminar Flow Water Film

A plasma mirror based on a laminar water film with low flow speed 0.5-2 cm/s has been developed and characterized, for use as an ultrahigh intensity optical reflector. The use of flowing water as atarget surface automatically results in each laser pulse seeing a new interaction surface and avoids the need for mechanical scanning of the target surface. In addition, the breakdown of water does notproduce contaminating debris that can be deleterious to vacuum chamber conditions and optics, such as is the case when using conventional solid targets. The mirror exhibits 70percent reflectivity, whilemaintaining high-quality of the reflected spot.
Date: July 22, 2011
Creator: Panasenko, Dmitriy; Shu, Anthony J.; Gonsalves, Anthony; Nakamura, Kei; Matlis, Nicholas H.; Toth, Csaba et al.
System: The UNT Digital Library
Tape-Drive Based Plasma Mirror (open access)

Tape-Drive Based Plasma Mirror

We present experimental results on a tape-drive based plasma mirror which could be used for a compact coupling of a laser beam into a staged laser driven electron accelerator. This novel kind of plasma mirror is suitable for high repetition rates and for high number of laser shots. In order to design a compact, staged laser plasma based accelerator or collider [1], the coupling of the laser beam into the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters (cf. Fig 1). The fluence of the laser pulse several centimeters away from the acceleration stage (focus) exceeds the damage threshold of any available mirror coating. Therefore, in reference [2] a plasma mirror was suggested for this purpose. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage. Plasma mirrors composed of antireflection coated glass substrates are usually used to improve the temporal laser contrast of laser pulses by several orders of magnitudes [3,4]. This is particularly important for laser …
Date: July 22, 2011
Creator: Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei et al.
System: The UNT Digital Library
MIX and Instability Growth from Oblique Shock (open access)

MIX and Instability Growth from Oblique Shock

We have studied the formation and evolution of shock-induced mix resulting from interface features in a divergent cylindrical geometry. In this research a cylindrical core of high-explosive was detonated to create an oblique shock wave and accelerate the interface. The interfaces studied were between the high-explosive/aluminum, aluminum/plastic, and finally plastic/air. Pre-emplaced surface features added to the aluminum were used to modify this interface. Time sequence radiographic imaging quantified the resulting instability formation from the growth phase to over 60 {micro}s post-detonation. Thus allowing the study of the onset of mix and evolution to turbulence. The plastic used here was porous polyethylene. Radiographic image data are compared with numerical simulations of the experiments.
Date: July 22, 2011
Creator: Molitoris, J D; Batteux, J D; Garza, R G; Tringe, J W; Souers, P C & Forbes, J W
System: The UNT Digital Library
From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions (open access)

From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions

We discuss a standard model of heavy ion collisions that has emerged both from experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electro-Ion Collider.
Date: July 22, 2010
Creator: Venugopalan, R.
System: The UNT Digital Library
A molecularly defined duplication set for the X chromosome of Drosophila melanogaster (open access)

A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

We describe a molecularly defined duplication kit for the X chromosome of Drosophila melanogaster. A set of 408 overlapping P[acman] BAC clones was used to create small duplications (average length 88 kb) covering the 22-Mb sequenced portion of the chromosome. The BAC clones were inserted into an attP docking site on chromosome 3L using C31 integrase, allowing direct comparison of different transgenes. The insertions complement 92% of the essential and viable mutations and deletions tested, demonstrating that almost all Drosophila genes are compact and that the current annotations of the genome are reasonably accurate. Moreover, almost all genes are tolerated at twice the normal dosage. Finally, we more precisely mapped two regions at which duplications cause diplo-lethality in males. This collection comprises the first molecularly defined duplication set to cover a whole chromosome in a multicellular organism. The work presented removes a long-standing barrier to genetic analysis of the Drosophila X chromosome, will greatly facilitate functional assays of X-linked genes in vivo, and provides a model for functional analyses of entire chromosomes in other species.
Date: July 22, 2010
Creator: Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W. et al.
System: The UNT Digital Library
Human Factors Engineering Program Review Model (NUREG-0711)Revision 3: Update Methodology and Key Revisions (open access)

Human Factors Engineering Program Review Model (NUREG-0711)Revision 3: Update Methodology and Key Revisions

The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) programs of applicants for nuclear power plant construction permits, operating licenses, standard design certifications, and combined operating licenses. The purpose of these safety reviews is to help ensure that personnel performance and reliability are appropriately supported. Detailed design review procedures and guidance for the evaluations is provided in three key documents: the Standard Review Plan (NUREG-0800), the HFE Program Review Model (NUREG-0711), and the Human-System Interface Design Review Guidelines (NUREG-0700). These documents were last revised in 2007, 2004 and 2002, respectively. The NRC is committed to the periodic update and improvement of the guidance to ensure that it remains a state-of-the-art design evaluation tool. To this end, the NRC is updating its guidance to stay current with recent research on human performance, advances in HFE methods and tools, and new technology being employed in plant and control room design. NUREG-0711 is the first document to be addressed. We present the methodology used to update NUREG-0711 and summarize the main changes made. Finally, we discuss the current status of the update program and the future plans.
Date: July 22, 2012
Creator: Ohara J. M.; Higgins, J. & Fleger, S.
System: The UNT Digital Library
A molecularly defined duplication set for the X chromosome of Drosophila melanogaster (open access)

A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

None
Date: July 22, 2010
Creator: Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W. et al.
System: The UNT Digital Library
External and Internal Guest Binding of a Highly Charged Supramolecular Host in Water: Deconvoluting the Very Different Thermodynamics (open access)

External and Internal Guest Binding of a Highly Charged Supramolecular Host in Water: Deconvoluting the Very Different Thermodynamics

NMR, UV-vis and isothermal titration calorimetry (ITC) measurements probe different aspects of competing host-guest equilibria as simple alkylammonium guest molecules interact with both the exterior (ion-association) and interior (encapsulation) of the [Ga{sub 4}L{sub 6}]{sup 12-} supramolecular assembly in water. Data obtained by each independent technique measure different components of the host-guest equilibria and only when analyzed together does a complete picture of the solution thermodynamics emerge. Striking differences between the internal and external guest binding are found. External binding is enthalpy driven and mainly due to attractive interactions between the guests and the exterior surface of the assembly while encapsulation is entropy driven as a result of desolvation and release of solvent molecules from the host cavity.
Date: July 22, 2009
Creator: Sgarlata, Carmelo; Mugridge, Jeffrey; Pluth, Michael; Tiedemann,, Bryan; Zito, Valeria; Arena, Giuseppe et al.
System: The UNT Digital Library
AN EXPERIMENTAL STUDY OF THE EFFECT OF OPERATOR HANDS ON THE REACTIVITY OF A FAST METAL SYSTEM (open access)

AN EXPERIMENTAL STUDY OF THE EFFECT OF OPERATOR HANDS ON THE REACTIVITY OF A FAST METAL SYSTEM

None
Date: July 22, 2011
Creator: Percher, C & Heinrichs, D
System: The UNT Digital Library
Lawrence Livermore National Laboratory Plutonium Facility Personal Nuclear Accident Dosimeter (open access)

Lawrence Livermore National Laboratory Plutonium Facility Personal Nuclear Accident Dosimeter

None
Date: July 22, 2011
Creator: Wysong, A R; Hickman, D P; Wong, C T; Heinrichs, D P; Scorby, J C & Merritt, M J
System: The UNT Digital Library