27 Matching Results

Search Results

Beam manipulation and compression using broadband rf systems in the Fermilab Main Injector and Recycler

Description: A novel method for beam manipulation, compression, and stacking using a broad band RF system in circular accelerators is described. The method uses a series of linear voltage ramps in combination with moving barrier pulses to azimuthally compress, expand, or cog the beam. Beam manipulations can be accomplished rapidly and, in principle, without emittance growth. The general principle of the method is discussed using beam dynamics simulations. Beam experiments in the Fermilab Recycler Ring convincingly validate the concept. Preliminary experiments in the Fermilab Main Injector to investigate its potential for merging two ''booster batches'' to produce high intensity proton beams for neutrino and antiproton production are described.
Date: July 9, 2004
Creator: al., G William Foster et
Partner: UNT Libraries Government Documents Department

Long-Lifetime Low-Scatter Neutron Polarization Target

Description: Polarized neutrons scattering is an important technology for characterizing magnetic and other materials. Polarized helium three (P-3He) is a novel technology for creating polarized beams and, perhaps more importantly, for the analysis of polarization in highly divergent scattered beams. Analysis of scattered beams requires specialized targets with complex geometries to ensure accurate results. Special materials and handling procedures are required to give the targets a long useful lifetime. In most cases, the targets must be shielded from stray magnetic fields from nearby equipment. SRL has developed and demonstrated hybrid targets made from glass and aluminum. We have also developed and calibrated a low-field NMR system for measuring polarization lifetimes. We have demonstrated that our low-field system is able to measure NMR signals in the presence of conducting (metallic) cell elements. We have also demonstrated a non-magnetic valve that can be used to seal the cells. We feel that these accomplishments in Phase I are sufficient to ensure a successful Phase II program. The commercial market for this technology is solid. There are over nine neutron scattering centers in the US and Canada and over 22 abroad. Currently, the US plans to build a new $1.4B scattering facility called the Spallation Neutron Source (SNS). The technology developed in this project will allow SRL to supply targets to both existing and future facilities. SRL is also involved with the application of P-3He to medical imaging.
Date: July 9, 2004
Creator: Richardson, Dr. Jonathan M.
Partner: UNT Libraries Government Documents Department

Radiation Effects in Nuclear Waste Materials

Description: The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials.
Date: July 9, 2004
Creator: Weber, William j.; Wang, Lumin & Icenhower, Jonathan
Partner: UNT Libraries Government Documents Department

Mineral Sequestration of Carbon Dixoide in a Sandstone-Shale System

Description: A conceptual model of CO2 injection in bedded sandstone-shale sequences has been developed using hydrogeologic properties and mineral compositions commonly encountered in Gulf Coast sediments. Numerical simulations were performed with the reactive fluid flow and geochemical transport code TOUGHREACT to analyze mass transfer between sandstone and shale layers and CO2 immobilization through carbonate precipitation. Results indicate that most CO2 sequestration occurs in the sandstone. The major CO2 trapping minerals are dawsonite and ankerite. The CO2 mineral-trapping capacity after 100,000 years reaches about 90 kg per cubic meter of the medium. The CO2 trapping capacity depends on primary mineral composition. Precipitation of siderite and ankerite requires Fe+2 supplied mainly by chlorite and some by hematite dissolution and reduction. Precipitation of dawsonite requires Na+ provided by oligoclase dissolution. The initial abundance of chlorite and oligoclase therefore affects the CO2 mineral trapping capacity. The sequestration time required depends on the kinetic rate of mineral dissolution and precipitation. Dawsonite reaction kinetics is not well understood, and sensitivity regarding the precipitation rate was examined. The addition of CO2 as secondary carbonates results in decreased porosity. The leaching of chemical constituents from the interior of the shale causes slightly increased porosity. The limited information currently available for the mineralogy of natural high-pressure CO2 gas reservoirs is also generally consistent with our simulation. The ''numerical experiments'' give a detailed understanding of the dynamic evolution of a sandstone-shale geochemical system.
Date: July 9, 2004
Creator: Xu, Tianfu; Apps, John A. & Pruess, Karsten
Partner: UNT Libraries Government Documents Department

Synchronization of the Fermilab Booster and Main Injector for multiple batch injection

Description: To date, the 120 GeV Fermilab Main Injector accelerator has accelerated a single batch of protons from the 8 GeV rapid-cycling Booster synchrotron for production of antiprotons for Run II. In the future, the Main Injector must accelerate 6 or more Booster batches simultaneously; the first will be extracted to the antiproton source, while the remaining are extracted for the NuMI/MINOS (Neutrinos at the Main Injector/Main Injector Neutrino Oscillation Search) neutrino experiment. Performing this multi-batch operation while avoiding unacceptable radioactivation of the beamlines requires a previously unnecessary synchronization between the accelerators. We describe a mechanism and present results of advancing or retarding the longitudinal progress of the Booster beam by active feedback radial manipulation of the beam during the acceleration period.
Date: July 9, 2004
Creator: al., Robert Zwaska et
Partner: UNT Libraries Government Documents Department

Mutual Funds: SEC Should Modify Proposed Regulations to Address Some Pension Plan Concerns

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Mutual fund investments represent more than 20 percent of Americans' pension plan assets. Since late 2003, two abusive trading practices in mutual funds have come to light. Late trading allowed some investors to illegally place orders for funds after the close of trading. Market timing allowed some investors to take advantage of temporary disparities between the value of a fund and the value of its underlying assets despite stated policies against such trading. The Securities and Exchange Commission (SEC) has proposed regulations intended to stop late trading and reduce market timing. We were asked to (1) report on what is known about how these practices have affected the value of retirement savings of pension plan participants, (2) describe the actions taken by SEC and the Department of Labor (DOL) to address these practices, and (3) explain how plan participants may be affected by SEC's proposed regulations."
Date: July 9, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Critical Infrastructure Protection: Improving Information Sharing with Infrastructure Sectors

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Critical infrastructure protection (CIP) activities called for in federal policy and law are intended to enhance the security of the public and private infrastructures that are essential to our nation's security, economic security, and public health and safety. Effective information-sharing partnerships between industry sectors and government can contribute to CIP efforts. Federal policy has encouraged the voluntary creation of information sharing and analysis centers (ISAC) to facilitate infrastructure sector participation in CIP information sharing efforts. GAO was asked to identify actions that the Department of Homeland Security (DHS) could take to improve the effectiveness of CIP information-sharing efforts."
Date: July 9, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Bonneville Power Administration: Better Management of BPA's Obligation to Provide Power Is Needed to Control Future Costs

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Bonneville Power Administration (BPA) has experienced significant financial problems in recent years. BPA's cash reserves at the end of fiscal year 2002 had fallen to $188 million, and BPA estimated in February 2003 that it had a 74 percent chance of missing its Treasury debt payment that year. While BPA's finances have recently improved, and the agency made its Treasury payment in 2003, BPA's financial condition is still far from robust. In this context, GAO was asked to report on (1) the advantages and disadvantages BPA faces in marketing electric power in a more competitive environment, (2) the major causes of BPA's recent cost increases, and (3) the extent to which BPA is taking actions to control its costs."
Date: July 9, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Follow-Up on GAO Recommendations Concerning the Securities Investor Protection Corporation

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "This letter responds to a Congressional request that GAO report on the status of our recommendations relating to the Securities and Exchange Commission's (SEC) oversight of the Securities Investor Protection Corporation (SIPC) and investor education. As requested, this letter also includes information on SIPC's progress in implementing SEC's recommendations from its January 2003 examination of SIPC and the status of excess SIPC coverage. Specifically, GAO'S objectives were to (1) determine the status of our recommendations to SEC and SIPC from our two previous reports on SIPC, (2) review recent actions SIPC has taken to address recommendations from the 2003 SEC examination report, and (3) determine the status of excess SIPC coverage after three U.S. insurers ceased offering the product."
Date: July 9, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

FY 2005 Annual Report on the Cooperative Threat Reduction Program

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "Under section 1308 of the National Defense Authorization Act for Fiscal Year 2001 (P.L. 106-398), the Department of Defense (DOD) is to submit an annual report to Congress on its Cooperative Threat Reduction (CTR) program no later than the first Monday in February of each year. The report should include a 5-year plan that discusses the amount and purpose of funding needed over the term of the plan and a description of efforts conducted by the United States to ensure that CTR assistance is fully accounted for and used for its intended purposes. The act requires the Comptroller General to assess this 5-year plan and the description of efforts to account for CTR assistance within 90 days of the report's submission to Congress. The Department submitted its CTR annual report for fiscal year 2005 to Congress in early February 2004, and we briefed Congressional staff on April 29, 2004. We analyzed the 2005 report to determine whether (1) the 5-year plan addresses legislative requirements and presents accurate information, (2) the accountability section addresses legislative requirements and presents accurate information, and (3) past GAO recommendations have been adopted."
Date: July 9, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Technical Scope and Approach for the 2004 Composite Analysis of Low Level Waste Disposal at the Hanford Site

Description: A composite analysis is required by U.S. Department of Energy (DOE) Manual 435.1-1 to ensure public safety through the management of active and planned low-level radioactive waste disposal facilities associated with the Hanford Site (DOE/HQ-Manual 435.1-1). A Composite Analysis is defined as ''a reasonably conservative assessment of the cumulative impact from active and planned low-level waste disposal facilities, and all other sources from radioactive contamination that could interact with the low-level waste disposal facility to affect the dose to future members of the public''. At the Hanford Site, a composite analysis is required for continued disposal authorization for the immobilized low-activity waste, tank waste vitrification plant melters, low level waste in the 200 East and 200 West Solid Waste Burial Grounds, and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) waste in the Environmental Restoration Disposal Facility. The 2004 Composite Analysis will be a site-wide analysis, considering final remedial actions for the Columbia River corridor and the Central Plateau at the Hanford Site. The river corridor includes waste sites and facilities in each of the 100 Areas as well as the 300, 400, and 600 Areas. The remedial actions for the river corridor are being conducted to meet residential land use standards with the vision of the river corridor being devoted to a combination of recreation and preservation. The ''Central Plateau'' describes the region associated with operations and waste sites of the 200 Areas. DOE is developing a strategy for closure of the Central Plateau area by 2035. At the time of closure, waste management activities will shrink to a Core Zone within the Central Plateau. The Core Zone will contain the majority of Hanford's permanently disposed waste
Date: July 9, 2004
Creator: Kincaid, Charles T.; Bryce, Robert W. & Buck, John W.
Partner: UNT Libraries Government Documents Department

Satiated relative permeability of variable-aperture fractures

Description: Experimental studies of capillary-dominated displacements in variable-aperture fractures have demonstrated the occurrence of a satiated state at the end of invasion, where significant entrapment of the displaced phase occurs. The structure of this entrapped phase controls the behavior of flow and transport processes in the flowing phase. Recent studies have shown that the areal saturation of the flowing phase at satiation (S{sub f}) is largely controlled by a single parameter C/{delta}, where C, the Curvature number, weighs the mean in-plane interfacial curvature relative to the mean out-of-plane interfacial curvature, and {delta}, the coefficient of variation of the aperture field, represents the strength of interface roughening induced by aperture variations. Here we consider the satiated relative permeability (k{sub rs}) to the flowing phase, which is defined as the relative permeability at satiation, when the defending phase is fully entrapped. The satiated relative permeability is shown to be a well-defined function of S{sub f} over a wide range of C/{delta}, ranging from capillary fingering with significant entrapment (C/{delta} {yields} 0) to smooth invasion with very little entrapment (C/{delta} > 1). We propose a relationship, based on effective medium theory, for the satiated relative permeability as a function of S{sub f}. The predicted relative permeability values are accurate across the entire range of phase structures representative of capillary dominated displacements in variable-aperture fractures.
Date: July 9, 2004
Creator: Detwiler, R L; Rajaram, H & Glass, R J
Partner: UNT Libraries Government Documents Department

Study of the Uncertainty on Compton Ring Reconstruction

Description: The purpose of this study was to estimate the effect of measurement errors in the position and energy of the observed interactions on the angular resolution of a Compton-ring imaging type detector. In a Compton interaction, if one can measure the energy of the scattered photon and the energy of the Compton electron, then one can determine the scattering angle between the incoming and outgoing photon using the well-known Compton formula.
Date: July 9, 2004
Creator: Gronberg, J B; Johnson, S C; Lange, D J & Wright, D M
Partner: UNT Libraries Government Documents Department

[Letter from Emily Gray to Charles Francis, June 9, 2004]

Description: A letter from Emily Gray to Charles C. Francis inviting him to attend the 2004 Republican National Convention in New York City as part of the Bush's "Friends and Family" program. The letter contains information for lodgings and transportation and mentions a reservation and questionnaire to fill out as well as one if Francis is unable to attend.
Date: July 9, 2004
Creator: Gray, Emily
Partner: UNT Libraries Special Collections

Study of Compton vs. Photoelectric Interactions

Description: We have studied how often incoming photons interact via a Compton interaction and/or a photoelectric interaction as a function of energy and detector material Results are using a 1m{sup 3} detector, and discrete energy photons from 0.1 MeV up to 10 MeV. Essentially all of the lower energy photons interact at least once in a detector of this size. This is not the case at higher energies. Each detector, photon energy combination was simulated with 2000 photons.
Date: July 9, 2004
Creator: Gronberg, J B; Johnson, S C; Lange, D J; Wright, D M & Beiersdorfer, P
Partner: UNT Libraries Government Documents Department

Theoretical Modelling of the Diffuse Emission of (gamma)-rays From Extreme Regions of Star Formation: The Case of Arp 220

Description: Our current understanding of ultraluminous infrared galaxies suggest that they are recent galaxy mergers in which much of the gas in the former spiral disks, particularly that located at distances less than 5 kpc from each of the pre-merger nuclei, has fallen into a common center, triggering a huge starburst phenomenon. This large nuclear concentration of molecular gas has been detected by many groups, and estimates of molecular mass and density have been made. Not surprisingly, these estimates were found to be orders of magnitude larger than the corresponding values found in our Galaxy. In this paper, a self-consistent model of the high energy emission of the super-starburst galaxy Arp 220 is presented. The model also provides an estimate of the radio emission from each of the components of the central region of the galaxy (western and eastern extreme starbursts, and molecular disk). The predicted radio spectrum is found as a result of the synchrotron and free-free emission, and absorption, of the primary and secondary steady population of electrons and positrons. The latter is output of charged pion decay and knock-on leptonic production, subject to a full set of losses in the interstellar medium. The resulting radio spectrum is in agreement with sub-arcsec radio observations, what allows to estimate the magnetic field. In addition, the FIR emission is modeled with dust emissivity, and the computed FIR photon density is used as a target for inverse Compton process as well as to give account of losses in the {gamma}-ray scape. Bremsstrahlung emission and neutral pion decay are also computed, and the {gamma}-ray spectrum is finally predicted. Future possible observations with GLAST, and the ground based Cherenkov telescopes are discussed.
Date: July 9, 2004
Creator: Torres, D F
Partner: UNT Libraries Government Documents Department

Enhancing Seismic Calibration Research Through Software Automation

Description: The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Engineering (GNEM R&E) Program has made significant progress enhancing the process of deriving seismic calibrations and performing scientific integration with automation tools. We present an overview of our software automation efforts and framework to address the problematic issues of very large datasets and varied formats utilized during seismic calibration research. The software and scientific automation initiatives directly support the rapid collection of raw and contextual seismic data used in research, provide efficient interfaces for researchers to measure/analyze data, and provide a framework for research dataset integration. The automation also improves the researcher's ability to assemble quality controlled research products for delivery into the NNSA Knowledge Base (KB). The software and scientific automation tasks provide the robust foundation upon which synergistic and efficient development of, GNEM R&E Program, seismic calibration research may be built. The task of constructing many seismic calibration products is labor intensive and complex, hence expensive. However, aspects of calibration product construction are susceptible to automation and future economies. We are applying software and scientific automation to problems within two distinct phases or 'tiers' of the seismic calibration process. The first tier involves initial collection of waveform and parameter (bulletin) data that comprise the 'raw materials' from which signal travel-time and amplitude correction surfaces are derived and is highly suited for software automation. The second tier in seismic research content development activities include development of correction surfaces and other calibrations. This second tier is less susceptible to complete automation, as these activities require the judgment of scientists skilled in the interpretation of often highly unpredictable event observations. Even partial automation of this second tier, through development of prototype tools to extract observations and make many thousands of scientific measurements, has significantly increased the efficiency of the ...
Date: July 9, 2004
Creator: Ruppert, S; Dodge, D; Elliott, A; Ganzberger, M; Hauk, T; Matzel, E et al.
Partner: UNT Libraries Government Documents Department