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Speckle Imaging Over Horizontal Paths (open access)

Speckle Imaging Over Horizontal Paths

Atmospheric aberrations reduce the resolution and contrast in surveillance images recorded over horizontal or slant paths. This paper describes our recent horizontal and slant path imaging experiments of extended scenes as well as the results obtained using speckle imaging. The experiments were performed with an 8-inch diameter telescope placed on either a rooftop or hillside and cover ranges of interest from 0.5 km up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures. The improvement in image quality using speckle imaging is dramatic in many cases, and depends significantly upon the atmospheric conditions. We quantify resolution improvement through modulation transfer function measurement comparisons.
Date: May 21, 2002
Creator: Carrano, C J
System: The UNT Digital Library
An integrated mechanical design concept for the final focusingregion for the HIF point design (open access)

An integrated mechanical design concept for the final focusingregion for the HIF point design

A design study was undertaken to develop a ''first cut'' integrated mechanical design concept of the final focusing region for a conceptual IFE power plant that considers the major issues which must be addressed in an integrated driver and chamber system. The conceptual design in this study requires a total of 120 beamlines located in two conical arrays attached on the sides of the target chamber 180 degrees apart. Each beamline consists of four large-aperture superconducting quadrupole magnets and a dipole magnet. The major interface issues include radiation shielding and thermal insulation of the superconducting magnets; reaction of electromagnetic loads between the quadrupoles; alignment of the magnets; isolation of the vacuum regions in the target chamber from the beamline, and assembly and maintenance.
Date: November 21, 2002
Creator: Brown, T.; Sabbi, G. L.; Barnard, J. J.; Heitzenroeder, P.; Chun, J.; Schmidt, J. et al.
System: The UNT Digital Library
Rates and technologies for mass-market demand response (open access)

Rates and technologies for mass-market demand response

Demand response programs are often quickly and poorlycrafted in reaction to an energy crisis and disappear once the crisissubsides, ensuring that the electricity system will be unprepared whenthe next crisis hits. In this paper, we propose to eliminate theevent-driven nature of demand response programs by considering demandresponsiveness a component of the utility obligation to serve. As such,demand response can be required as a condition of service, and theoffering of demand response rates becomes a requirement of utilities asan element of customer service. Using this foundation, we explore thecosts and benefits of a smart thermostat-based demand response systemcapable of two types of programs: (1) a mandatory, system-operatorcontrolled, contingency program, and (2) a voluntary, customercontrolled, bill management program with rate-based incentives. Anydemand response program based on this system could consist of either orboth of these components. Ideally, these programs would be bundled,providing automatic load management through customer-programmed priceresponse, plus up to 10 GW of emergency load shedding capability inCalifornia. Finally, we discuss options for and barriers toimplementation of such a program in California.
Date: July 21, 2002
Creator: Herter, Karen; Levy, Roger; Wilson, John & Rosenfeld, Arthur
System: The UNT Digital Library
Detailed spectroscopic analysis of SN 1987A: The distance to the LMC using the SEAM method (open access)

Detailed spectroscopic analysis of SN 1987A: The distance to the LMC using the SEAM method

Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model the observed spectra from Day 1 to Day 81 using a hydrodynamical model. We show that good agreement can be obtained at times up to about 60 days, if we allow for extended nickel mixing. Later than about 60 days the observed Balmer lines become stronger than our models can reproduce. We show that this is likely due to a more complicated distribution of gamma-rays than we allow for in our spherically symmetric calculations. We present synthetic light curves in UBVRIJHK and a synthetic bolometric light curve. Using this broad baseline of detailed spectroscopic models we find a distance modulus mu = 18.5 +/- 0.2 using the SEAM method of determining distances to supernovae. We find that the explosion time agrees with that of the neutrino burst and is constrained at 68 percent confidence to within +/- 0.9 days. We argue that the weak Balmer lines of our detailed model calculations casts doubt on the accuracy of the purely photometric EPM method. We also suggest that Type IIP supernovae will be most useful …
Date: May 21, 2002
Creator: Mitchell, Robert C.; Baron, E.; Branch, David; Hauschildt, Peter H.; Nugent, Peter E.; Lundqvist, Peter et al.
System: The UNT Digital Library
Characterization of Spatial Variability of Hydrogeologic Properties for Unsaturated Flow in the Fractured Rocks at Yucca Mountain, Nevada (open access)

Characterization of Spatial Variability of Hydrogeologic Properties for Unsaturated Flow in the Fractured Rocks at Yucca Mountain, Nevada

The spatial variability of layer-scale hydrogeologic properties of the unsaturated zone (UZ) at Yucca Mountain, Nevada, is investigated using inverse modeling. The thick UZ is grouped into five hydrostratigraphic units and further into 35 hydrogeologic layers. For each layer, lateral variability is represented by the variations in calibrated values of layer-scale properties at different individual deep boreholes. In the calibration model, matrix and fracture properties are calibrated for the one-dimensional vertical column at each individual borehole using the ITOUGH2 code. The objective function is the summation of the weighted misfits between the ambient unsaturated flow (represented by measured state variables: water saturation, water potential, and pneumatic pressure) and the simulated one in the one-dimensional flow system. The objective function also includes the weighted misfits between the calibrated properties and their prior information. Layer-scale state variables and prior rock properties are obtained from their core-scale measurements. Because of limited data, the lateral variability of three most sensitive properties (matrix permeability, matrix of the van Genuchten characterization, and fracture permeability) is calibrated, while all other properties are fixed at their calibrated layer-averaged values. Considerable lateral variability of hydrogeologic properties is obtained. For example, the lateral variability of is two to three orders …
Date: May 21, 2002
Creator: Zhou, Quanlin; Bodvarsson, Gudmundur S.; Liu, Hui-Hai & Oldenburg, Curtis M.
System: The UNT Digital Library
Estimating subsurface topography from surface-to-borehole seismic studies at the Rye Patch Geothermal Reservoir (open access)

Estimating subsurface topography from surface-to-borehole seismic studies at the Rye Patch Geothermal Reservoir

None
Date: May 21, 2002
Creator: Gritto, Roland; Daley, Thomas M. & Majer, Ernest L.
System: The UNT Digital Library
Betatron motion with coupling of horizontal and vertical degrees of freedom (open access)

Betatron motion with coupling of horizontal and vertical degrees of freedom

The Courant-Snyder parameterization of one-dimensional linear betatron motion is generalized to two-dimensional coupled linear motion. To represent the 4 x 4 symplectic transfer matrix the following ten parameters were chosen: four beta-functions, four alpha-functions and two betatron phase advances which have a meaning similar to the Courant-Snyder parameterization. Such a parameterization works equally well for weak and strong coupling and can be useful for analysis of coupled betatron motion in circular accelerators as well as in transfer lines. Similarly, the transfer matrix, the bilinear form describing the phase space ellipsoid and the second order moments are related to the eigen-vectors. Corresponding equations can be useful in interpreting tracking results and experimental data.
Date: November 21, 2002
Creator: Bogacz, S. A. & Lebedev, V. A.
System: The UNT Digital Library
The future of fixed target physics : Snowmass E5 working group summary. (open access)

The future of fixed target physics : Snowmass E5 working group summary.

None
Date: January 21, 2002
Creator: Kumar, K.; Ray, R.; Reimer, R. & Strovink, M.
System: The UNT Digital Library
Electroweak Prospects for Tevatron RunII (open access)

Electroweak Prospects for Tevatron RunII

In RunI each experiment collected about 100 pb{sup -1} of data. During RunIIa, each experiment is expected to collect about 2 fb{sup -1} of data. The center-of-mass energy for RunII, {radical}s = 2.0 TeV, is a bit larger than the 1.8 TeV of RunI and results in an increase of about 10% (35%) in the production cross-sections for W and Z (t{bar t}) events. Additional gains in the event yield are expected due to improvements in the detector acceptance and performance. Taken together, the RunIIa upgrades are expected to yield 2300k (800) W (t{bar t}) events per experiment, including the effects of event selection and triggering, which can be compared to the RunI yields of 77k (20) events. With the RunI data-set, CDF and D0 produced a breadth of electroweak results and obtained the world's only sample of top quarks. While the RunII electroweak physics program is very similar, the RunII upgrade improvements should yield many precision results. The Tevatron began delivering steady data in about June, 2001. The first six months of data taking was ''commissioning dominated'' for CDF and D0. Starting around January, 2002, the experiments were largely commissioned and began taking ''analysis quality'' data. The physics results …
Date: October 21, 2002
Creator: Glenzinski, D.
System: The UNT Digital Library
U.S. Department of Energy sponsored in-depth safety assessments of VVER and RBMK reactors. (open access)

U.S. Department of Energy sponsored in-depth safety assessments of VVER and RBMK reactors.

None
Date: February 21, 2002
Creator: Petri, M. C. & Pasedag, W. F.
System: The UNT Digital Library
NEUTRINO SUPER BEAM FACILITY FOR A LONG BASELINE EXPERIMENT FROM BNL TO HOMESTAKE. (open access)

NEUTRINO SUPER BEAM FACILITY FOR A LONG BASELINE EXPERIMENT FROM BNL TO HOMESTAKE.

An upgrade to the BNL Alternate Gradient Synchrotron (AGS) could produce a very intense proton source at a relatively low cost. Such a proton beam could be used to generate a conventional neutrino beam with a significant flux at large distances from the laboratory. This provides the possibility of a very long baseline neutrino experiment at the Homestake mine. The construction of this facility would allow a program of experiments to study many of the aspects of neutrino oscillations including CP violations. This study examines a 1 MW proton source at BNL and a large 1 megaton detector positioned at the Homestake Mine as the ultimate goal of a staged program to study neutrino oscillations.
Date: October 21, 2002
Creator: Kahn, S.
System: The UNT Digital Library
The control architecture of the D0 experiment (open access)

The control architecture of the D0 experiment

From a controls viewpoint, contemporary high energy physics collider detectors are comparable in complexity to small to medium size accelerators: however, their controls requirements often differ significantly. D0, one of two collider experiments at Fermilab, has recently started a second, extended running period that will continue for the next five years. EPICS [1], an integrated set of software building blocks for implementing a distributed control system, has been adapted to satisfy the slow controls needs of the D0 detector by (1) extending the support for new device types and an additional field bus, (2) by the addition of a global event reporting system that augments the existing EPICS alarm support, and (3) by the addition of a centralized database with supporting tools for defining the configuration of the control system. This paper discusses the control architecture of the current D0 experiment, how the EPICS system was extended to meet the control requirements of a large, high-energy physics detector, and how a formal control system contributes to the management of detector operations.
Date: November 21, 2002
Creator: al., J. Fredrick Bartlett et
System: The UNT Digital Library
TEM characterization of GaN nanowires (open access)

TEM characterization of GaN nanowires

Transmission electron microscopy was applied to study GaN nanowires grown on carbon nanotube surfaces by chemical reaction between Ga{sub 2}O and NH{sub 3} gas in a conventional furnace. These wires grew in two crystallographic directions, <2{und 11}0> and <01{und 1}0> (fast growth directions of GaN), in the form of whiskers covered by small elongated GaN platelets. The morphology of these platelets is similar to that observed during the growth of single crystals from a Ga melt at high temperatures under high nitrogen pressure. It is thought that growth of nanowires in two different crystallographic directions and the arrangement of the platelets to the central whisker may be influenced by the presence of Ga{sub 2}O{sub 3} (based on the observation of the energy dispersive x-ray spectra), the interplanar spacings in the wire, and the presence of defects on the interface between the central part of the nanowire and the platelets surrounding it.
Date: February 21, 2002
Creator: Liliental-Weber, Zuzanna; Gao, Y.H. & Bando, Y.
System: The UNT Digital Library
Towards a coherent theory of physics and mathematics. (open access)

Towards a coherent theory of physics and mathematics.

None
Date: January 21, 2002
Creator: Benioff, P.
System: The UNT Digital Library
Plasma considerations in the IPNS RCS. (open access)

Plasma considerations in the IPNS RCS.

Significant ionization appears to occur in the Rapid Cycling Synchrotron (RCS) during its 14 ms acceleration period leading to plasma formation and neutralization. The beam may in fact be over-neutralized, causing the tune to increase during the acceleration cycle. The overall tune shift in the RCS appears to be close to +0.5. The presence of plasma may help explain why longitudinal phase modulation can so quickly couple to transverse motion. In addition, plasmas tend to be inductive and the RCS appears to exhibit a relatively high inductance. Measurements of the electron cloud and plasma densities adjacent to the beam should be made. In addition to the RFA and Swept Analyzer diagnostics mentioned at the Workshop, other techniques might be attempted. If plasma is present, then a small, biased-probe might be useful (e.g., a Langmuir probe), or with the proper choice of geometry, an optics-based measurement for line density (e.g., an interferometer) might be employed, perhaps using microwaves for increased sensitivity.
Date: February 21, 2002
Creator: Dooling, J. C.; McMichael, G. E. & Brumwell, F. R.
System: The UNT Digital Library
The Physics of transmutation systems : system capabilities and performances. (open access)

The Physics of transmutation systems : system capabilities and performances.

This document is complementary to a document produced by Prof. Salvatores on ''The Physics of Transmutation in Critical or Subcritical Reactors and the Impact on the Fuel Cycle''. In that document, Salvatores describes the fundamental of transmutation, through basic physics properties and general parametric studies. In the present document we try to go one step further towards practical implementation (while recognizing that the practical issues such as technology development and demonstration, and economics, can only be mentioned in a very superficial manner). Section 1 briefly overviews the possible objectives of transmutation systems, and links these different objectives to possible technological paths. It also describes the overall constraints which have to be considered when developing and implementing transmutation systems. In section 2 we briefly overview the technological constraints which need to be accounted for when designing transmutation systems. In section 3 we attempt to provide a simplified classification of transmutation systems in order to clarify later comparisons. It compares heterogeneous and homogeneous recycle strategies, and single and multi-tier systems. Section 4 presents case analyses for assessing the transmutation performance of various individual systems, starting with LWR's (1. generic results; 2. multirecycle of plutonium; 3. an alternative: transmutation based on a Thorium …
Date: August 21, 2002
Creator: Finck, P. J.
System: The UNT Digital Library
Fabrication of biaxially textured templates for coated conductors by inclined substrate deposition. (open access)

Fabrication of biaxially textured templates for coated conductors by inclined substrate deposition.

YBCO-coated conductors will enable the development of smaller, lighter, more-efficient electric power devices that can be operated at temperatures approaching that of liquid nitrogen. The critical current density (J{sub c}) of YBCO films on flexible metallic substrates has been significantly improved by epitaxially growing the YBCO on biaxially textured template films. Inclined substrate deposition (ISD) offers the potential for rapidly producing high-quality biaxially textured buffer layers that are suitable for YBCO-coated conductors. Using the ISD method, we have grown biaxially textured MgO films at deposition rates of 20-100 {angstrom}/sec. Electron microscopy of the ISD-MgO films revealed columnar grains topped off by MgO (002) planes, and X-ray pole figure analysis showed that the (002) planes are tilted with respect to the substrate normal, giving ISD-MgO films a roof-tile surface morphology. A small phi-scan full-width at half maximum of {approx}10{sup o} was observed on ISD-MgO films deposited with a substrate inclination of 55{sup o}. YBCO films were grown on ISD-MgO buffered Hastelloy substrates by pulsed laser deposition. A sample that was 0.42 {micro}m x 0.45 mm x 1 cm gave a transport J{sub c} of {approx}0.34 MA/cm{sup 2} at 77 K in self-field. Details of ISD-MgO film fabrication and characterization, as well …
Date: August 21, 2002
Creator: Dorris, S. E.; Ma, B.; Li, M.; Fisher, B. L.; Koritala, R. E.; Erck, R. et al.
System: The UNT Digital Library
Use of superconducting bearings to measure the polarization of the cosmic microwave background radiation. (open access)

Use of superconducting bearings to measure the polarization of the cosmic microwave background radiation.

Measurements of the polarization of the cosmic microwave background (CMB) radiation are expected to significantly increase our understanding of the early universe. We present a design for a CMB polarimeter in which a cryogenically cooled half wave plate rotates by means of a high-temperature superconducting (HTS) bearing. The design is optimized for implementation in MAXIPOL, a balloon-borne CMB polarimeter. A prototype bearing, consisting of commercially available ring-shaped permanent magnet and an array of YBCO bulk HTS material, has been constructed. We report on measurements of the coefficient of friction as a function of temperature between 15 and 80 K, of rotation frequency between 0.3 and 3.5 Hz, of levitation distance between 6 and 10 mm, and of ambient pressure between 1 and 10{sup -7} torr. The low rotational drag of the HTS bearing allows rotations for long periods of time with minimal input power and negligible wear and tear thus making this technology suitable for a future satellite mission.
Date: August 21, 2002
Creator: Hanany, S.; Matsumura, T.; Johnson, B.; Jones, T.; Hull, J. R. & Ma, K. B.
System: The UNT Digital Library
Multiparticle dynamics in the E-phi tracking code ESME (open access)

Multiparticle dynamics in the E-phi tracking code ESME

ESME has developed over a twenty year period from its origins as a program for modeling rf gymnastics to a rather general facility for that fraction of beam dynamics of synchrotrons and storage rings which can be properly treated in the two dimensional longitudinal phase space. The features of this program which serve particularly for multiparticle calculations are described, some underling principles are noted, and illustrative results are given.
Date: June 21, 2002
Creator: MacLachlan, James A.
System: The UNT Digital Library
205 kA pulse power supply for neutrino focusing horns (open access)

205 kA pulse power supply for neutrino focusing horns

A new underground beamline is being constructed at Fermilab to generate and focus a beam of neutrinos on a detector 450 miles away in Soudan, Minnesota. A compact modulator utilizing capacitive energy storage and SCRs as the switching element has been built and tested at Fermilab. The 0.9 F capacitor bank operates at less than 1 kV. It delivers its output of up to 240 kA directly to the two series connected focusing horns via a multi-layer radiation hard stripline [1]. Dual pulse width capability allows for ready selection of 5.2 ms, for slow beam spills, or 2.6 ms operation for reduced thermal stresses on the focusing horns during fast spill. Intended for installation in an underground equipment room, the design incorporates several novel features to facilitate transport, installation, and maintenance. Various designs were examined to arrive at the most economical approach for providing the high pulse currents to the horns located in the very high radiation field, up to 3 x 10{sup 7} kRads/yr absorbed dose of the beamline. These included charge recovery and electronic polarity reversal systems. The direct coupling approach was selected for its overall economy and compactness. The system has been operational for several months and …
Date: June 21, 2002
Creator: Kenneth R. Bourkland, Kevin Roon and David Tinsley
System: The UNT Digital Library
Dense cermet membranes for hydrogen separation. (open access)

Dense cermet membranes for hydrogen separation.

Argonne National Laboratory (ANL) and the National Energy Technology Laboratory (NETL) are developing dense ceramic-based membranes for separating hydrogen from the products of coal gasification and other partial-oxidation streams. Hydrogen separation with these membranes is nongalvanic, i.e., it does not use electrodes or an external power supply to drive the separation, and hydrogen selectivity is nearly 100% because the membranes contain no interconnected porosity. Novel cermet (i.e., ceramic-metal composite) membranes have been developed to separate hydrogen from gas mixtures at high temperature and pressure. Hydrogen permeation rates have been measured in the temperature range of 600-900 C for three classes of cermet membranes (ANL-1, -2, and -3). ANL-3a membranes, with a thickness of 40 {micro}m, provide the highest hydrogen flux ({approx}20 cm{sup 3} [STP]/min-cm 2 at 900 C with 100% H{sub 2} as the feed gas). The effects of membrane thickness and hydrogen partial pressure on hydrogen flux indicate that the bulk diffusion of hydrogen is rate-limiting in ANL-3 membranes with a thickness >40 {micro}m. ANL-3b membranes were tested in simulated syngas at several temperatures, and no performance degradation was observed for times that approached {approx}200 h; this observation suggests that the membrane is chemically stable and may be suitable …
Date: August 21, 2002
Creator: Dorris, S. E.; Lee, T. H.; Wang, S.; Picciolo, J. J.; Dusek, J. T.; Balachandran, U. et al.
System: The UNT Digital Library
Regulatory Off-Gas Analysis from the Evaporator of Hanford Simulated Waste Spiked with Organic Compounds (open access)

Regulatory Off-Gas Analysis from the Evaporator of Hanford Simulated Waste Spiked with Organic Compounds

After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods.
Date: August 21, 2002
Creator: Calloway, T.B.
System: The UNT Digital Library
Search for MSSM Higgses at the Tevatron (open access)

Search for MSSM Higgses at the Tevatron

We present an overview of searches for MSSM Higgs at the Tevatron, concentrating on searches probing the high tan {beta} region. We discuss the search for A/H {yields} {tau}{tau} which is soon to be completed in the Run I data and review the new tau triggers implemented by CDF and D0 in Run II, which will greatly impact this analysis. We also present the results of a Run I search for A/Hbb {yields} bbbb performed by CDF and highlight expected improvements in this channel by both experiments in Run II.
Date: October 21, 2002
Creator: Connolly, A.
System: The UNT Digital Library
ET-based mixed-donor CT salt : [ET/MET/MT](ReO{sub 4}). (open access)

ET-based mixed-donor CT salt : [ET/MET/MT](ReO{sub 4}).

A new charge-transfer(CT) salt of the ET-based mixed-donor, [ET/MET/MT](ReO{sub 4}), has been prepared by the electrocrystallization. This salt has been revealed to be a 1:1 salt by x-ray structure analysis and micro-Raman spectroscopy. EPR measurement gives g = 2.007 and {_}H{sub pp} = 9.18G at 300K. It shows a semiconducting behavior with E{sub g} = 92-110 meV depending on the samples.
Date: August 21, 2002
Creator: Noh, D.-Y.; Han, Y.-K.; Kang, W.; Kang, H. & Geiser, U.
System: The UNT Digital Library