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Ags Proposal 923 - Search for T Violating Muon Polarization in K+ Yields M+p0vm Decay. (open access)

Ags Proposal 923 - Search for T Violating Muon Polarization in K+ Yields M+p0vm Decay.

None
Date: September 30, 1996
Creator: Diwan, M. V.; Frank, J.; Gordeev, A.; Kettell, S.; Leipuner, L.; Littenberg, L. et al.
System: The UNT Digital Library
Design studies for a high-resolution, transportable neutron radiography/radioscopy system (open access)

Design studies for a high-resolution, transportable neutron radiography/radioscopy system

A preliminary design has been developed for a high-resolution, transportable neutron radiology system (TNRS) concept. The primary system requirement is taken to be a thermal neutron flux of 10[sup 6] n/(cm[sup 2]-sec) with a L/D ratio of 100. The approach is to use an accelerator-driven neutron source, with a radiofrequency quadrupole (RFQ) as the primary accelerator component. Initial concepts for all of the major components of the system have been developed,and selected key parts have been examined further. An overview of the system design is presented, together with brief summaries of the concepts for the ion source, low energy beam transport (LEBT), RFQ, high energy beam transport (HEBT), target, moderator, collimator, image collection, power, cooling, vacuum, structure, robotics, control system, data analysis, transport vehicle, and site support. The use of trade studies for optimizing the TNRS concept are also described.
Date: September 30, 1996
Creator: Gillespie, G.H.; Micklich, B.J. & McMichael, G.E.
System: The UNT Digital Library
Relating x-ray attenuation measurements to water content and distribution in SB-15D core (open access)

Relating x-ray attenuation measurements to water content and distribution in SB-15D core

Making improved estimates of the water content of The Geysers reservoir is fundamental to efficient and economic long term production of steam power from the resource. A series of coordinated physical properties measurements form core recovered from the SB-15D, reported in this volume in a series of papers, have been made to better understand water storage and to relate water content and distribution to observable geophysical properties such as electrical conductivity and seismic velocities. A principal objective here is to report new interpretations of x-ray scans made within 72 hours of core recovery from SB-15D, which suggest, taking advantage of preliminary measurements of capillary suction for metagraywacke, that water content was low in much of the preserved core.
Date: September 30, 1996
Creator: Bonner, B. P.; Roberts, J. J. & Schneberk, D. J
System: The UNT Digital Library
Performance based vs. compliance based auditing: The similarities and the differences (open access)

Performance based vs. compliance based auditing: The similarities and the differences

Princeton University`s Plasma Physics Laboratory (PPPL) is a world leader in research associated with plasma science including the use of materials, the development of future fusion devices, and the application of plasma techniques in industry. At PPPL, one of Quality Assurance`s responsibilities includes the internal audit/appraisal program. In early FY95 a task force, including representation from internal customers, was created to improve the program and to assure that the program better supports the mission of the Laboratory. One of the most significant changes recommended by the task force was to move from a compliance based auditing program to a performance based program. A trial of this change was successfully performed in fiscal year 1995. Because of the success of the trial, this change was adopted as standard practice. Today, a scheduled audit may be performance based, compliance based, or a combination of the two as determined jointly by the Quality Assurance Manager and the management of the program to be audited. This paper discusses the similarities and differences between these two types of audits. Both audits are performed to effect improvements in the program being audited. However, compliance based audits focus on compliance issues with the risk of missing performance …
Date: September 26, 1996
Creator: Malsbury, J. A.
System: The UNT Digital Library
Controlling our destinies: Historical, philosophical, social and ethical perspectives on the Human Genome Project: Final report, July 1, 1995-June 30, 1996 (open access)

Controlling our destinies: Historical, philosophical, social and ethical perspectives on the Human Genome Project: Final report, July 1, 1995-June 30, 1996

This report briefly describes the efforts by the organizing committee in preparation for the conference entitled Controlling Our Destinies: Historical, Philosophical, Social, and Ethical Perspectives on the Human Genome Project. The conference was held October 5-8, 1995.
Date: September 25, 1996
Creator: Sloan, P.R.
System: The UNT Digital Library
Energy gain of highly charged ions in front of LiF (open access)

Energy gain of highly charged ions in front of LiF

We present estimates of the energy gain of highly charged ions approaching a LiF surface, based on a modified classical-over-barrier model for insulators. The analysis includes the energy gain by image acceleration as well as the deceleration due to charge-up of the surface in a staircase sequence. The role of the frequency-dependent dielectric response of LiF is emphasized. The resulting velocity dependent total energy gain is studied in detail and the results are compared with experimental data.
Date: September 24, 1996
Creator: Haegg, L.; Reinhold, C. O. & Burgdoerfer, J.
System: The UNT Digital Library
Extensible message passing application development and debugging with Python (open access)

Extensible message passing application development and debugging with Python

The authors describe how they have parallelized Python, an interpreted object oriented scripting language, and used it to build an extensible message-passing C/C++ applications for the CM-5, Cray T3D, and Sun multiprocessor servers running MPI. Using a parallelized Python interpreter, it is possible to interact with large-scale parallel applications, rapidly prototype new features, and perform application specific debugging. It is even possible to write message passing programs in Python itself. The authors describe some of the tools they have developed to extend Python and applications of this approach.
Date: September 19, 1996
Creator: Beazley, David M. & Lomdahl, Peter S.
System: The UNT Digital Library
3-D electromagnetic modeling of wakefields in accelerator components (open access)

3-D electromagnetic modeling of wakefields in accelerator components

We discuss the use of 3-D finite-difference time-domain (FDTD) electromagnetic codes for modeling accelerator components. Computational modeling of cylindrically symmetric structures such as induction accelerator cells has been very successful in predicting the wake potential and wake impedances of these structures, but full 3-D modeling of complex structures has been limited due to substantial computer resources required for a full 3-D model. New massively parallel 3-D time domain electromagnetic codes now under development using conforming unstructured meshes allow a substantial increase in the geometric fidelity of the structures being modeled. Development of these new codes are discussed in context of applicability to accelerator problems. Various 3-D structures are tested with an existing cubical cell FDTD code and wake impedances compared with simple analytic models for the structures; results will be used as benchmarks for testing the new time time domain codes. Structures under consideration include a stripline beam position monitor as well as circular and elliptical apertures in circular waveguides. Excellent agreement for monopole and dipole impedances with models were found for these structures below the cutoff frequency of the beam line.
Date: September 18, 1996
Creator: Poole, B.R.; Caporaso, G.J.; Ng, Wang C.; Shang, C.C. & Steich, D.
System: The UNT Digital Library
CP violation in top physics at the NLC (open access)

CP violation in top physics at the NLC

Top quark is extremely sensitive to non-standard CP violating phases. General strategies for exposing different types of phases at the NLC are outlined. SUSY phase(s) cause PRA in t {yields} Wb. The transverse polarization of the {tau} in the reaction t {yields} b{tau}{nu} is extremely sensitive to a phase from the charged Higgs sector. Phase(s) from the neutral Higgs sector cause appreciable dipole moment effects and lead to sizable asymmetries in e{sup +}e{sup {minus}} {yields} t{anti t}H{sup 0} and e{sup +}e{sup {minus}} {yields} t{anti t}{nu}{sub e}{anti {nu}}{sub e}.
Date: September 18, 1996
Creator: Atwood, D. & Soni, A.
System: The UNT Digital Library
Understanding the nonlinear beam dynamics of the Advanced Light Source (open access)

Understanding the nonlinear beam dynamics of the Advanced Light Source

Frequency map analysis is used to study the single particle transverse beam dynamics in ALS. The maps, which provide details about the diffusion of orbits and limits on long term stability, are generated by a postprocessor attached to a tracking code. This paper describes the method and shows how the map is changed when the 12- fold symmetry of the linear lattice is perturbed by including measured magnetic field imperfections. Also the long term stability of orbits that reside in regions of large diffusion is studied.
Date: September 18, 1996
Creator: Robin, D. & Laskar, J.
System: The UNT Digital Library
Quark masses, chiral symmetry, and the U(1) anomaly (open access)

Quark masses, chiral symmetry, and the U(1) anomaly

The author discusses the mass parameters appearing in the gauge theory of the strong interactions, concentrating on the two flavor case. He shows how the effect of the CP violating parameter {theta} is simply interpreted in terms of the state of the aether via an effective potential for meson fields. For degenerate flavors he shows that a first order phase transition is expected at {theta} = {pi}. The author speculates on the implications of this structure for Wilson`s lattice fermions.
Date: September 17, 1996
Creator: Creutz, M.
System: The UNT Digital Library
Report of the Supersymmetry Theory Subgroup (open access)

Report of the Supersymmetry Theory Subgroup

We provide a mini-guide to some or the possible manifestations of weak scale supersymmetry. For each of six scenarios we provide: a brief description of the theoretical underpinnings, the adjustable parameters, a qualitative description of the associated phenomenology at future colliders, comments on how to simulate each scenario with existing event generators,
Date: September 17, 1996
Creator: Amundson, J.; Anderson, G. & Baer, H.
System: The UNT Digital Library
Wilson fermions at finite temperature (open access)

Wilson fermions at finite temperature

The author conjectures on the phase structure expected for lattice gauge theory with two flavors of Wilson fermions, concentrating on large values of the hopping parameter. Numerous phases are expected, including the conventional confinement and deconfinement phases, as well as an Aoki phase with spontaneous breaking of flavor and parity and a large hopping phase corresponding to negative quark masses.
Date: September 17, 1996
Creator: Creutz, M.
System: The UNT Digital Library
Flavor changing neutral currents and the third family (open access)

Flavor changing neutral currents and the third family

We consider a Two Higgs Doublet Model with Flavor Changing Scalar Neutral Currents arising at the tree level. All the most important constraints are taken into account and the compatibility with the present Electroweak measurements is examined. The Flavor Changing couplings involving the third family are not constrained to be very small and this allows us to predict some interesting signals of new physics.
Date: September 16, 1996
Creator: Reina, L.
System: The UNT Digital Library
The Conservation Reserve Program as a Means to Subsidize Bioenergy Crop Prices (open access)

The Conservation Reserve Program as a Means to Subsidize Bioenergy Crop Prices

The Conservation Reserve Program (CRP), enacted in the 1985 Farm Bill, removes environmentally sensitive cropland from production in exchange for annual rental payments from the federal government. To reduce the cost of the program, economic use of CRP acres in exchange for reduced rental payments were proposed, but not implemented in the 1995 Farm Bill. This paper examines the potential impact an economic use policy would have on the market prices of bioenergy crops if they were permitted to be harvested from CRP acres. The analysis shows that at average yields of 11.25 dry Mg/ha/yr (5 dry tons/ac/yr) and total production of 9.1 million dry Mg (10 million dry tons) subsidized farmgate prices of as low as $16.5/dry Mg ($15/dry ton) for switchgrass and $24.2/dry Mg ($22/dry ton) for short-rotation woody crops can be achieved. Furthermore, the government can reduce the cost of the CRP resulting in a potential win-win situation.
Date: September 15, 1996
Creator: Walsh, M.E.; Becker, D. & Graham, R.L.
System: The UNT Digital Library
ORRECL-Oak Ridge Energy Crop County Level Database (open access)

ORRECL-Oak Ridge Energy Crop County Level Database

None
Date: September 15, 1996
Creator: Graham, R. L.; Allison, L. J. & Becker, D. A.
System: The UNT Digital Library
Transportation and Site Location Analysis for Regional Integrated Biomass Assessment (RIBA) (open access)

Transportation and Site Location Analysis for Regional Integrated Biomass Assessment (RIBA)

The farmgate cost and available supply of biomass often exhibit considerable variation within a State. This variation, combined with the relatively high cost of transporting bulky biomass material, produces a wide range of expected delivered feedstock costs across a State. As a consequence, both production and transportation costs must be well-modeled when analyzing potential locations for conversion facilities. The Regional Integrated Biomass Assessment system consists of two phases. The descriptive phase characterizes a farmgate cost and supply surface for switchgrass production over a given State. These results are passed to the analytical phase, where a transportation model is used to compute the marginal cost of supplying an ethanol plant at a prescribed level of demand. The model generates a marginal cost surface that illustrates the most promising areas for locating an ethanol plant. Next, a sequential location model simulates the commercial development of ethanol production facilities. This model considers every road network node as a potential site and generates a sequence of likely plant locations. Results from the RIBA analysis demonstrate that the cost of switchgrass can increase dramatically from one location to another. This variation will seriously effect the economics of conversion in the proper sizing and locating of …
Date: September 15, 1996
Creator: Noon, C. E.; Daly, M. J.; Graham, R. L. & Zahn, F. B.
System: The UNT Digital Library
Solubility of Anthracene in Binary Alkane + Methyl tert-Butyl Ether Solvent Mixtures at 298.15 K (open access)

Solubility of Anthracene in Binary Alkane + Methyl tert-Butyl Ether Solvent Mixtures at 298.15 K

Article on the solubility of anthracene in binary alkane + methyl tert-butyl ether solvent mixtures at 298.15 K.
Date: September 12, 1996
Creator: McHale, Mary E. R.; Kauppila, Ann-Sofi M. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Solubility of Benzil in Binary Alkane + Methyl tert-Butyl Ether Solvent Mixtures (open access)

Solubility of Benzil in Binary Alkane + Methyl tert-Butyl Ether Solvent Mixtures

Article on the solubility of benzil in binary alkane + methyl tert-butyl ether solvent mixtures.
Date: September 12, 1996
Creator: McHale, Mary E. R.; Powell, Joyce R.; Kauppila, Ann-Sofi M. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Conceptual design for a neutron imaging system for thick target analysis operating in the 10-15 MeV energy range (open access)

Conceptual design for a neutron imaging system for thick target analysis operating in the 10-15 MeV energy range

Fast neutron imaging offers the potential to be a powerful non- destructive inspection tool for evaluating the integrity of thick sealed targets. This is particularly true in cases where one is interested in detecting voids, cracks or other defects in low-Z materials (e.g. plastics, ceramics, salts, etc.) which are shielded by thick, high-Z parts. In this paper we present the conceptual design for a neutron imaging system for use in the 10 - 15 MeV energy range and discuss potential applications in the area of nuclear stockpile steward- ship. The background of this project, currently under development at LLNL, will be outlined and computer simulations will be presented which predict system performance. Efforts to assess technical risks involved in the development of the system will be discussed and the results of a recent experiment designed to evaluate background radiation levels will also be presented.
Date: September 11, 1996
Creator: Dietrich, F.; Hall, J. & Logan, C.
System: The UNT Digital Library
High-Resolution Superconducting X-Ray Spectrometers With an Active Area of 282 μm x 282 μm (open access)

High-Resolution Superconducting X-Ray Spectrometers With an Active Area of 282 μm x 282 μm

Superconducting tunnel junctions coupled to superconducting absorbers may be used as high-resolution, high-efficiency X-ray spectrometers. We have tested devices with niobium X-ray absorbing layers coupled to aluminum layers that serve as quasiparticle traps. In this work we measured the current pulses from a large area tunnel junction using an amplifier based on an array of 100 SQUIDs. Using this amplifier and a 282 micron X 282 micron junction, we have measured an energy resolution of 19 eV FWHM for 1.5 keV X rays and 21 eV for 2.6 keV X rays. The area of this junction is eight times the area of any junction previously measured to have such high energy resolution.
Date: September 11, 1996
Creator: Mears, C. A.; Labov, S. E.; Frank, M.; Netel, H.; Hiller, L. J.; Lindeman, M. A. et al.
System: The UNT Digital Library
Isolated prompt photon cross sections (open access)

Isolated prompt photon cross sections

We show that the conventionally defined partonic cross section for the production of isolated prompt photons is not an infrared safe quantity. We work out the case of {ital e}{sup +}{ital e}{sup -} {r_arrow} {gamma} + {Chi}, and discuss implications for hadron reactions.
Date: September 11, 1996
Creator: Berger, E. L.; Guo, Xiaofeng & Qiu, Jianwei
System: The UNT Digital Library
Depleted uranium oxides and silicates as spent nuclear fuel waste package fill materials (open access)

Depleted uranium oxides and silicates as spent nuclear fuel waste package fill materials

A new repository waste package (WP) concept for spent nuclear fuel (SNF) is being investigated that uses depleted uranium (DU) to improve performance and reduce the uncertainties of geological disposal of SNF. The WP would be filled with SNF and then filled with depleted uranium (DU) ({approximately}0.2 wt % {sup 235}U) dioxide (UO{sub 2}) or DU silicate-glass beads. Fission products and actinides can not escape the SNF UO{sub 2} crystals until the UO{sub 2} dissolves or is transformed into other chemical species. After WP failure, the DU fill material slows dissolution by three mechanisms: (1) saturation of AT groundwater with DU and suppression of SNF dissolution, (2) maintenance of chemically reducing conditions in the WP that minimize SNF solubility by sacrificial oxidation of DU from the +4 valence state, and (3) evolution of DU to lower-density hydrated uranium silicates. The fill expansion seals the WP from water flow. The DU also isotopically exchanges with SNF uranium as the SNF degrades to reduce long-term nuclear-criticality concerns.
Date: September 10, 1996
Creator: Forsberg, Charles W.
System: The UNT Digital Library
Discovery mass reach for excited quarks at hadron colliders (open access)

Discovery mass reach for excited quarks at hadron colliders

If quarks are composite particles then excited states are expected. We estimate the discovery mass reach as a function of integrated luminosity for excited quarks decaying to dijets at the Tevatron the mass reach is 0.94 TeV for Run 11 (2 fb{sup -1}) and 1. 1 TeV for TeV33 (30 fb{sup -1}). At the LHC the mass reach is 6.3 TeV for 100 fb{sup -1}. At a VLHC with a center of mass energy {radical}s, of 50 TeV (200 TeV) the mass reach is 25 TeV (78 TeV) for an integrated luminosity of 10{sup 4} fb{sup -1}. However, an excited quark with a mass of 25 TeV would be discovered at a hadron collider with {radical}s = 100 TeV and an integrated luminosity of 13 fb{sup -1}, illustrating a physics example where a factor of 2 in machine energy is worth a factor of 1000 in luminosity.
Date: September 10, 1996
Creator: Harris, R.M.
System: The UNT Digital Library