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Analysis of Events Associated with First Charge of Desicooler Material

Description: HB-Line's mission included dissolution of uranium-aluminum scrap left over from a U3O8 scrap recovery program begun in 1972 with material returned from Rocky Flats and Oak Ridge. This material has been stored in desicooler containers, and is commonly referred to as the Desicoolers. The Scrap Recovery process includes the dissolution of scrap material and transfer of the resulting solution to H-Canyon for further disposition. During the first charge of this material into the HB-Line dissolvers, the solution heated to boiling without external heat being added. Yellow-colored fumes, which dissipated rapidly, were noted in the glovebox by operators, and a small amount of liquid was noted in the glovebox by operations after dissolver cooldown. This technical report documents analysis of the data from the event with respect to potential Safety Basis violation and the Integrated Safety Management System process. Based on the analysis presented, the safety basis has shown its ability to protect the worker, the facility and the public.
Date: September 15, 2003
Creator: Alexander, D.E.
Partner: UNT Libraries Government Documents Department

Search for top and bottom squarks

Description: Searches for the lightest scalar top quark {bar t}{sub 1} and scalar bottom quark {bar b}{sub 1} performed at LEP2 with a center-of-mass energy of up to {radical}s = 209 GeV and at Tevatron using data collected at {radical}s = 1.8 TeV during Run I and at {radical}s = 1.96 TeV during Run II, are discussed. Different possible decay modes were considered and no evidence for any such signal was observed. Exclusion limits were extracted.
Date: October 15, 2003
Creator: Rott, C.
Partner: UNT Libraries Government Documents Department

Grid-based Parallel Data Streaming Implemented for the Gyrokinetic Toroidal Code

Description: We have developed a threaded parallel data streaming approach using Globus to transfer multi-terabyte simulation data from a remote supercomputer to the scientist's home analysis/visualization cluster, as the simulation executes, with negligible overhead. Data transfer experiments show that this concurrent data transfer approach is more favorable compared with writing to local disk and then transferring this data to be post-processed. The present approach is conducive to using the grid to pipeline the simulation with post-processing and visualization. We have applied this method to the Gyrokinetic Toroidal Code (GTC), a 3-dimensional particle-in-cell code used to study microturbulence in magnetic confinement fusion from first principles plasma theory.
Date: September 15, 2003
Creator: Klasky, S.; Ethier, S.; Lin, Z.; Martins, K.; McCune, D. & Samtaney, R.
Partner: UNT Libraries Government Documents Department

Effects of Resin Particle Size and Solution Temperature on SuperLig(R) 644 Resin Performance with AN-105 Simulate

Description: The performance of the SuperLig(R) 644 resin loading and elution was evaluated at 25, 35, and 45 degree C using a single-column containing 2.25 g of oven-dry, hydrogen form of SuperLig(R) 664 resin. A simulated Envelope A solution was used to mimic the composition of low-activity waste solution from Tank 241-AN-105 supernate in the Hanford Site waste tank. The simulant was spiked with small quantities of trace metals (cadmium, chromium, iron, and lead) to evaluate the effects of these metals on cesium sorption. The results from column tests performed at 25, 35, and 45 degree C showed that more than 100 BVs of simulated Envelope A solution could be processed at each temperature before 50 percent breakthrough of the cesium occurred.
Date: July 15, 2003
Creator: Nash, C.A.
Partner: UNT Libraries Government Documents Department

Scientific Basis for Monitored Natural Attenuation and Enhanced Passive Remediation for Chlorinated Solvents - DOE Alternative Project for Technology Acceleration Implementation Plan

Description: The overall Monitored Natural Attenuation and Enhanced Passive Remediation (MNA/EPR) Technology Alternative Project is narrowly focused, providing the scientific and policy support to facilitate implementing appropriate passive cleanup and cost effective monitoring strategies leading to responsible completion of active remediation activities at high risk DOE waste sites. MNA/EPR describe natural processes that mitigate exposure and risk and that are self-sustaining once implemented or require minimal adjustments to maintain functionality. The overall MNA/EPR project effort will be performed as a collaboration between DOE science and operations organizations at the target sites along with regulatory agencies, stakeholders, industry, and universities, as identified in the approved Alternative Project Plan. This plan describes the project initiation activities, individual roles and responsibilities, milestones, and budget for the project. A primary product of this project will be a collaboratively developed MNA/EPR protocol that will facilitate widespread use and acceptance. This technical protocol will be developed in collaboration with regulator agencies as input for regulation updates and guidance documents, as appropriate. This plan describes the project initiation activities, individual roles and responsibilities, milestones, and budget for the project.
Date: April 15, 2003
Creator: Vangelas, K.
Partner: UNT Libraries Government Documents Department

Higgs searches and prospects at CDF

Description: The Standard model of electroweak interactions (SM) has been extremely successful in describing interactions of elementary particles over the last decades. The Higgs scalar boson is one of the key elements of the SM: Higgs interactions with the other particles generate the particle masses and allow to keep the theory renormalizable at electroweak scale. All the particles predicted by the SM but the Higgs boson have already been observed experimentally and therefore search for the Higgs is one of the most important scientific goals for high energy physics. The current lower limit on the SM Higgs mass M{sub H} > 114.4 GeV at 95% CL has been established by LEP experiments. In this paper we review CDF Run I results on Higgs searches including the Higgs bosons predicted by the minimal supersymmetric extention of the Standard Model (MSSM) and discuss the Run II prospects.
Date: January 15, 2003
Creator: Murat, Pavel A
Partner: UNT Libraries Government Documents Department

Installation of Water Flux Meters to Measure the Temporal Variation in Water Flux Through the Vadose Zone

Description: The Savannah River Site has implemented a comprehensive vadose zone monitoring system at it's low level radioactive waste disposal facility in E-Area. The VSMS consists of nests of advanced tesiometers, water content reflectometers, suction lysimeters.
Date: January 15, 2003
Creator: Nichols, R.L.
Partner: UNT Libraries Government Documents Department

Noise propagation in iterative reconstruction algorithms with line searches

Description: In this paper we analyze the propagation of noise in iterative image reconstruction algorithms. We derive theoretical expressions for the general form of preconditioned gradient algorithms with line searches. The results are applicable to a wide range of iterative reconstruction problems, such as emission tomography, transmission tomography, and image restoration. A unique contribution of this paper comparing to our previous work [1] is that the line search is explicitly modeled and we do not use the approximation that the gradient of the objective function is zero. As a result, the error in the estimate of noise at early iterations is significantly reduced.
Date: November 15, 2003
Creator: Qi, Jinyi
Partner: UNT Libraries Government Documents Department

Studies with Ferrous Sulfamate and Alternate Reductants for 2nd Uranium Cycle

Description: A wide range of miniature mixer-settler tests were conducted to determine the source of iron and sulfur contamination in the uranium product stream (''1EU'') of H Canyon's 2nd Uranium Cycle. The problem was reproduced on the laboratory scale mixer-settlers by changing the feed location of ferrous sulfamate from stage D4 to stage D1. Other process variables effected no change. It was later determined that ferrous sulfamate (FS) solids had plugged the FS line to stage D4, causing FS to backup a ventline and enter the Canyon process at stage D1. Pluggage was almost certainly due to precipitation of FS solids during extended process downtime. During the search for the root cause, tests showed that FS solids were quite small (1-10 mm), and a portion of them could bypass the current Canyon prefilter (3-mm). Also, additional tests were done to find an alternate means of reducing and thereby removing plutonium and neptunium from the uranium product. These tests showed that FS was a more effective reductant than either ascorbic acid or a hydroxylamine nitrate (HAN) / dilute FS combination.
Date: January 15, 2003
Creator: Crowder, M.L.
Partner: UNT Libraries Government Documents Department

ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS

Description: This report documents the accident analyses and nuclear safety control options for use in Revision 7 of HNF-SD-WM-SAR-062, ''K Basins Safety Analysis Report'' and Revision 4 of HNF-SD-SNF-TSR-001, ''Technical Safety Requirements - 100 KE and 100 KW Fuel Storage Basins''. These documents will define the authorization basis for Sludge Water System (SWS) operations. This report follows the guidance of DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports'', for calculating onsite and offsite consequences. The accident analysis summary is shown in Table ES-1 below. While this document describes and discusses potential control options to either mitigate or prevent the accidents discussed herein, it should be made clear that the final control selection for any accident is determined and presented in HNF-SD-WM-SAR-062.
Date: November 15, 2003
Creator: Williams, J. C.
Partner: UNT Libraries Government Documents Department

CDF tau triggers, analysis and other developments

Description: This note is a write-up of contribution made by the author to the HCP2002 conference. It has two principal subjects. The first subject concerns the CDF {tau} triggers, {tau}-cone algorithms and {tau} physics analysis. {tau} physics is going to be very important in Run II because {tau}'s can extend SUSY searches at large tan {beta} in particular, {tau}'s will help in the searches for {tilde {chi}}{sub 1}{sup {+-}}{tilde {chi}}{sub 2}{sup 0}, MSSM Higgs and other non Standard Model (SM) processes. Also, {tau} events are important for various Standard Model processes including Precision Electroweak, t{bar t}, and SM Higgs searches. {tau} triggers are installed and operating at CDF. The second subject of this contribution to the HCP2002 conference concerns the algorithms of backwards differentiation abstracted from their usual setting inside of Automatic Differentiation software packages. Backwards differentiation (reverse-mode differentiation) provides a useful means for optimizing many kinds of problems.
Date: January 15, 2003
Creator: Smith, J. R.
Partner: UNT Libraries Government Documents Department

Sort-First, Distributed Memory Parallel Visualization and Rendering

Description: While commodity computing and graphics hardware has increased in capacity and dropped in cost, it is still quite difficult to make effective use of such systems for general-purpose parallel visualization and graphics. We describe the results of a recent project that provides a software infrastructure suitable for general-purpose use by parallel visualization and graphics applications. Our work combines and extends two technologies: Chromium, a stream-oriented framework that implements the OpenGL programming interface; and OpenRM Scene Graph, a pipelined-parallel scene graph interface for graphics data management. Using this combination, we implement a sort-first, distributed memory, parallel volume rendering application. We describe the performance characteristics in terms of bandwidth requirements and highlight key algorithmic considerations needed to implement the sort-first system. We characterize system performance using a distributed memory parallel volume rendering application, a nd present performance gains realized by using scene specific knowledge to accelerate rendering through reduced network bandwidth. The contribution of this work is an exploration of general-purpose, sort-first architecture performance characteristics as applied to distributed memory, commodity hardware, along with a description of the algorithmic support needed to realize parallel, sort-first implementations.
Date: July 15, 2003
Creator: Bethel, E. Wes; Humphreys, Greg; Paul, Brian & Brederson, J. Dean
Partner: UNT Libraries Government Documents Department

AMRNodeElliptic user guide: On rectangular problem domains

Description: This document describes an extension to the Chombo package [CGL+00] for solving elliptic equations using adaptive mesh refinement on multiple levels with node-centered data. See the AMRNodeElliptic design document [McC02] for a description of the algorithms used. Chapter 2 describes the class NodeFArrayBox and functions that use this class to manipulate node-centered data. Interfaces for elliptic equation solvers are described in chapter 3. Some internal classes of the solvers are described in chapter 4. User interfaces for physical boundary conditions are described in chapter 5. The AMRNodeElliptic package requires that Chombo library be installed. See chapter 1 of the Chombo design document [CGL+00] for requirements and installation of Chombo.
Date: April 15, 2003
Creator: McCorquodale, Peter
Partner: UNT Libraries Government Documents Department

Density Prediction of Uranium-6 Niobium Ingots

Description: The densities of uranium-6 niobium (U-Nb) alloys have been compiled from a variety of literature sources such as Y-12 and Rocky Flats datasheets. We also took advantage of the 42 well-pedigreed, homogeneous baseline U-Nb alloys produced under the Enhanced Surveillance Program for density measurements. Even though U-Nb alloys undergo two-phase transitions as the Nb content varies from 0 wt. % to 8 wt %, the theoretical and measured densities vary linearly with Nb content. Therefore, the effect of Nb content on the density was modeled with a linear regression. From this linear regression, a homogeneous ingot of U-6 wt.% Nb would have a density of 17.382 {+-} 0.040 g/cc (95% CI). However, ingots produced at Y-12 are not homogeneous with respect to the Nb content. Therefore, using the 95% confidence intervals, the density of a Y-12 produced ingot would vary from 17.310 {+-} 0.043 g/cc at the center to 17.432 {+-} 0.039 g/cc at the edge. Ingots with larger Nb inhomogeneities will also have larger variances in the density.
Date: April 15, 2003
Creator: D.F.Teter; Tubesing, P.K.; D.J.Thoma & E.J.Peterson
Partner: UNT Libraries Government Documents Department

Heavy baryons - Recent and very new results

Description: Recent results on observations, properties and decay modes of the charmed and beauty baryons will be reviewed. Candidates for several new high mass states which include a cleanly-identified daughter {Lambda}{sub c}{sup +} baryon are seen in data from the SELEX experiment at Fermilab. These states are candidates for doubly-charmed baryons: a {Xi}{sub cc}{sup ++} state and a {Xi}{sub cc}{sup +} state. These candidates are more than 5{sigma} signals in each case at masses of 3520 and 3460 MeV respectively.
Date: January 15, 2003
Creator: Cooper, Peter S
Partner: UNT Libraries Government Documents Department

Fiber-Optic Laser Raman Spectroscopy Sensor

Description: The Defense Programs Plant Directed Research and Development Program sponsored the optimization and interface of a fiber-optic Raman sensor as a complementary technique to mass spectrometry currently used in the Tritium Facility for measuring hydrogen isotopes. This sensor will provide real-time feedback while reducing the sample load for off-line gas analysis by the Tritium mass spectrometers. The compact Raman system incorporates a 488 nanometer laser system, spectrometer and detector along with a 20-foot fiber-optic probe. The analysis of gas mixtures of protium and deuterium at various compositions and total pressures ranging form 11 to 5000 torr showed good signal to noise ratios using very short integration times (15 seconds). The detection limits for protium and deuterium ranged from 0.5 percent to 0.8 percent. This probe will be demonstrated in-line in the new HT TCAP (hydrogen-tritium thermal cycling absorption process) cold runs.
Date: September 15, 2003
Creator: Ziegler, K.E.
Partner: UNT Libraries Government Documents Department

Special Analysis: Update of Disposal of Cement-Stabilized Encapsulated Waste at the E-Area Low-Level Waste Facility

Description: This Special Analysis for Components-in-Grout (CIG) expands the list of isotopes to the full suite of normal isotopes. This revision also addresses selected isotopes in special waste forms from the K and L basin resin that have waste-specific Kds and high-concentration I-129 wastes with waste-specific Kds, including Effluent Treatment Facility (ETF) activated carbon vessels. The full suite of normal isotopes was first screened using the Slit Trench screening results as a conservative approach. The isotopes that survived the screening were analyzed to determine the appropriate CIG inventory limits. The groundwater modeling was revised to incorporate improvements and changes in other recent Special Analyses and Unreviewed Disposal Question (UDQ) evaluations. The air pathway analysis was modified to consider a distributed source rather than a point source. These changes are discussed below in intruder and groundwater sections. Tables and figures are provided in appendices that are directly related to the most recent analyses. Changes to inventory limits are shown in Table 7. Inventory limits for solubility- limited radionuclides require special treatment as discussed in Section 3.1.1.3. U-238 and Pu-239 were analyzed as being solubility-limited, because otherwise they would consume excessive amounts of their inventory limits. Other U and Pu isotopes were not analyzed as being solubility- limited because they would not consume excessive amounts of inventory limits. Current and projected inventories for the K and L basin resins are compared against inventory limits for a single set of 5 CIG trenches. Projections for the K and L basin waste are through 2035, thus actual inventory consumption is dependent on the total number of CIG trenches excavated and filled through 2035. Current inventory for three ETF activated carbon vessels awaiting disposal are compared against inventory limits for a single set of 5 CIG trenches.
Date: October 15, 2003
Creator: Collard, L.B.
Partner: UNT Libraries Government Documents Department

Use of Modeling for the Prevention of Solids Formation During Canyon Processing of Legacy Nuclear Materials

Description: This report describes the effort to develop a predictive model of the stability of aqueous solutions of nuclear materials will enable the avoidance of concentrations that may cause salts to precipitate. Therefore, for the processing of off-normal material, the risk of producing unwanted solids that require processing to stop will be reduced. Processing delays result in higher operating costs. In addition, the improved model may reduce the work scope for future flowsheet development by identifying the concentration of dissolver solutions that avoid the precipitation of salts. As an initial impact, the improved INEEL model should reduce costs for the processing of difficult-to-dissolve residues from the Rocky Flats Environmental Technology Site by shortening the time it takes to determine dissolving solutions. As a long-term impact, this model should improve schedules to dissolve other off-normal nuclear materials and process aqueous solutions that are stored throughout the DOE complex.
Date: October 15, 2003
Creator: Rhodes, W.D.
Partner: UNT Libraries Government Documents Department

Field Performance of a Slimline Turbomist Evaporator under Southeastern U. S. Climate Conditions

Description: A recent study of evaporation technologies for treating F- and H-area groundwater contaminated with radionuclides and metals (Flach 2002) suggested that spray evaporation might be a viable alternative or supplemental technique for managing tritiated groundwater at the Mixed Waste Management Facility. The particular technology of interest in this study is the Slimline Manufacturing Ltd. Turbo-Mist Evaporator, which uses a powerful blower and high-pressure spray nozzles to propel a fine mist into the air at high air and water flowrates.
Date: December 15, 2003
Creator: Sappington, F.C.
Partner: UNT Libraries Government Documents Department

Propagation of errors from the sensitivity image in list mode reconstruction

Description: List mode image reconstruction is attracting renewed attention. It eliminates the storage of empty sinogram bins. However, a single back projection of all LORs is still necessary for the pre-calculation of a sensitivity image. Since the detection sensitivity is dependent on the object attenuation and detector efficiency, it must be computed for each study. Exact computation of the sensitivity image can be a daunting task for modern scanners with huge numbers of LORs. Thus, some fast approximate calculation may be desirable. In this paper, we theoretically analyze the error propagation from the sensitivity image into the reconstructed image. The theoretical analysis is based on the fixed point condition of the list mode reconstruction. The non-negativity constraint is modeled using the Kuhn-Tucker condition. With certain assumptions and the first order Taylor series approximation, we derive a closed form expression for the error in the reconstructed image as a function of the error in the sensitivity image. The result provides insights on what kind of error might be allowable in the sensitivity image. Computer simulations show that the theoretical results are in good agreement with the measured results.
Date: November 15, 2003
Creator: Qi, Jinyi & Huesman, Ronald H.
Partner: UNT Libraries Government Documents Department

Jet Physics at Tevatron

Description: An overview of Run I jet physics at the p{bar p} Fermilab Tevatron Collider with a particular emphasis on inclusive jet cross section measurements is given. The impact of these studies on PDFs constrain from global fits is underlined. Preliminary results on inclusive jet and di-jet mass cross section measurements in Run II are then summarized.
Date: December 15, 2003
Creator: Latino, G.
Partner: UNT Libraries Government Documents Department