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Fish Passage Through a Simulated Horizontal Bulb Turbine Pressure Regime: A Supplement to"Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish"

Description: Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including pressure changes during turbine passage. The responses of fall chinook salmon and bluegill sunfish to rapid pressure change was investigated at the Pacific Northwest National Laboratory. Previous test series evaluated the effects of passage through a vertical Kaplan turbine under the"worst case" pressure conditions and under less severe conditions where pressure changes were minimized. For this series of tests, pressure changes were modified to simulate passage through a horizontal bulb turbine, commonly installed at low head dams. The results were compared to results from previous test series. Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including pressure changes during turbine passage. The responses of fall chinook salmon and bluegill sunfish to rapid pressure change was investigated at the Pacific Northwest National Laboratory. Previous test series evaluated the effects of passage through a vertical Kaplan turbine under the"worst case" pressure conditions and under less severe conditions where pressure changes were minimized. For this series of tests, pressure changes were modified to simulate passage through a horizontal bulb turbine, commonly installed at low head dams. The results were compared to results from previous test series. Both fish species were acclimated for 16-22 hours at either surface (101 kPa; 1 atm) or 30 ft (191 kPa; 1.9 atm) of pressure in a hyperbaric chamber before exposure to a pressure scenario simulating passage through a horizontal bulb turbine. The simulation was as follows: gradual pressure increase to about 2 atm of pressure, followed by a sudden (0.4 second) decrease in pressure to either 0.7 or 0.95 atm, followed by gradual return to 1 atm (surface water pressure). Following the exposure, fish were held at surface …
Date: July 31, 2003
Creator: Abernethy, Cary S.; Amidan, Brett G. & Cada, G. F.
Partner: UNT Libraries Government Documents Department
open access

A brief examination of optical tagging technologies.

Description: Presented within this report are the results of a brief examination of optical tagging technologies funded by the Laboratory Directed Research and Development (LDRD) program at Sandia National Laboratories. The work was performed during the summer months of 2002 with total funding of $65k. The intent of the project was to briefly examine a broad range of approaches to optical tagging concentrating on the wavelength range between ultraviolet (UV) and the short wavelength infrared (SWIR, {lambda} < 2{micro}m). Tagging approaches considered include such things as simple combinations of reflective and absorptive materials closely spaced in wavelength to give a high contrast over a short range of wavelengths, rare-earth oxides in transparent binders to produce a narrow absorption line hyperspectral tag, and fluorescing materials such as phosphors, dies and chemically precipitated particles. One technical approach examined in slightly greater detail was the use of fluorescing nano particles of metals and semiconductor materials. The idea was to embed such nano particles in an oily film or transparent paint binder. When pumped with a SWIR laser such as that produced by laser diodes at {lambda}=1.54{micro}m, the particles would fluoresce at slightly longer wavelengths, thereby giving a unique signal. While it is believed that optical tags are important for military, intelligence and even law enforcement applications, as a business area, tags do not appear to represent a high on return investment. Other government agencies frequently shop for existing or mature tag technologies but rarely are interested enough to pay for development of an untried technical approach. It was hoped that through a relatively small investment of laboratory R&D funds, enough technologies could be identified that a potential customers requirements could be met with a minimum of additional development work. Only time will tell if this proves to be correct.
Date: July 1, 2003
Creator: Ackermann, Mark R.; Cahill, Paul A. (Aspecular Optics, Dayton, OH); Drummond, Timothy J. & Wilcoxon, Jess Patrick
Partner: UNT Libraries Government Documents Department
open access

Multi-strange baryon production in Au+Au collisions at {radical}s{sub NN} = 130 GeV

Description: The transverse mass spectra and mid-rapidity yields for {Xi}s and {Omega}s plus their anti-particles are presented. The 10% most central collision yields suggest that the amount of multi-strange particles produced per produced charged hadron increases from SPS to RHIC energies. A hydrodynamically inspired model fit to the spectra, which assumes a thermalized source, seems to indicate that these multi-strange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to {pi}, K, p and {lambda}s.
Date: July 30, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Multi-strange baryon production in Au-Au collisions at sqrt(sNN) = 130 GeV

Description: The transverse mass spectra and mid-rapidity yields for {Xi}s and {Omega}s plus their anti-particles are presented. The 10% most central collision yields suggest that the amount of multi-strange particles produced per produced charged hadron increases from SPS to RHIC energies. A hydrodynamically inspired model fit to the spectra, which assumes a thermalized source, seems to indicate that these multi-strange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to {pi}, K, p and {Lambda}s.
Date: July 31, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Fresnel Integral Equations: Numerical Properties

Description: A spatial-domain solution to the problem of electromagnetic scattering from a dielectric half-space is outlined. The resulting half-space operators are referred to as Fresnel surface integral operators. When used as preconditioners for nonplanar geometries, the Fresnel operators yield surface Fresnel integral equations (FIEs) which are stable with respect to dielectric constant, discretization, and frequency. Numerical properties of the formulations are discussed.
Date: July 22, 2003
Creator: Adams, R. J.; Champagne, N. J., (II) & Davis, B. A.
Partner: UNT Libraries Government Documents Department
open access

Supporting Dynamic Ad hoc Collaboration Capabilities

Description: Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.
Date: July 14, 2003
Creator: Agarwal, Deborah A. & Berket, Karlo
Partner: UNT Libraries Government Documents Department
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Scoping Inventory Calculations for the Rare Isotope Accelerator

Description: This document is a report on our activities in FY03 exploring nuclear safety and hazard analysis issues relevant to the Rare Isotope Accelerator (RIA). It is not clear whether DOE will classify the RIA as an accelerator facility subject to the accelerator-specific safety requirements of DOE Order 420.2A or as a nonreactor nuclear facility subject to the requirements of 10 CFR 830. The final outcome of this issue will have significant impact on the construction and operation of the facility and the quality assurance requirements for items or services that may affect nuclear safety. The resolution of this issue will be an important earlier decision for the RIA project team and will require early consultation with the appropriate DOE authorities. For nuclear facilities, facility hazard classification depends on the inventory of releasable radionuclides; therefore, some simplistic, scoping inventory calculations for some assumed targets and beams are done to estimate the hazard category of RIA if it is declared a nuclear facility. These calculations show that for the scenarios analyzed, RIA would produce sufficient quantities of radionuclides to be classified as a Category 3 nuclear facility. Over the lifetime of RIA operations, it may be possible to build up Category 2 quantities of {sup 227}Ac and {sup 228}Th. A storage building, separate from the driver, target, and experimental buildings, used to store and isolate accumulated targets and other hardware, can mitigate the potential impact on RIA. The more onerous requirements of Category 2 facilities would only be imposed on the storage facility and not on the rest of the RIA facilities. Some of the differences in a category 2 and category 3 facility are discussed in Appendix 1.
Date: July 25, 2003
Creator: Ahle, L. E. & Boles, J. L.
Partner: UNT Libraries Government Documents Department
open access

Coherent beam-beam effects, theory & observations

Description: Current theoretical understanding of the coherent beam-beam effect as well as its experimental observations are discussed: conditions under which the coherent beambeam modes may appear, possibility of their resonant interaction (coherent resonances), stability of beam-beam oscillations in the presence of external impedances. A special attention is given to the coherent beam-beam modes of finite length bunches: the synchro-betatron coupling is shown to provide reduction in the coherent tuneshift and--at the synchrotron tune values smaller than the beam-beam parameter--Landau damping by overlapping synchrotron satellites.
Date: July 16, 2003
Creator: Alexahin, Yuri I
Partner: UNT Libraries Government Documents Department
open access

Nonradiological Environmental Report Maamora Site, Morocco

Description: Under the Sister Laboratory Arrangement between Lawrence Livermore National Laboratory (LLNL) and the Moroccan National Center for Nuclear Energy Sciences and Techniques (CNESTEN), environmental sampling and analysis were performed to assess the background concentrations of nonradiological constituents in various environmental media at the Maamora Forest CNESTEN Laboratory Site. Samples were collected from surface soil, surface water and groundwater wells, short-lived vegetation (mainly native grass), and long-lived vegetation (cork oak). Samples were collected inside the property fence line, in the buffer zone surrounding the site, and off site at water locations. The soil and vegetation samples were analyzed for metals and pesticides and screened for polychlorinated biphenyls (PCBs); the water samples were analyzed for metals, general minerals, and pesticides and screened for PCBs.
Date: July 17, 2003
Creator: Althouse, P E; Blake, R G; Bandong, B B; Belghit, H & Dehbi, N
Partner: UNT Libraries Government Documents Department
open access

Guide to Individuals Seated on the Senate Dais

Description: This report is a brief summary of House and Senate procedures for reaching agreement on legislation. It discusses the provisions of House Rule XXII and Senate Rule XXVIII as well as other applicable rules, precedents, and practices. The report focuses on the most common and customary procedures.
Date: July 16, 2003
Creator: Amer, Mildred L.
Partner: UNT Libraries Government Documents Department
open access

A User's Guide to the Congressional Record

Description: The Congressional Record is a substantially verbatim account of remarks made during the proceedings of the House and Senate, subject only to technical, grammatical, and typographical corrections. It consists of four main sections: the proceedings of the House and Senate, the Extensions of Remarks, and the Daily Digest. This fact sheet is one of a series on the legislative process.
Date: July 17, 2003
Creator: Amer, Mildred L.
Partner: UNT Libraries Government Documents Department
open access

Synergia: A hybrid, parallel beam dynamics code with 3D space charge

Description: We describe Synergia, a hybrid code developed under the DOE SciDAC-supported Accelerator Simulation Program. The code combines and extends the existing accelerator modeling packages IMPACT and beamline/mxyzptlk. We discuss the design and implementation of Synergia, its performance on different architectures, and its potential applications.
Date: July 9, 2003
Creator: Amundson, James F. & Spentzouris, Panagiotis
Partner: UNT Libraries Government Documents Department
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Measurements of the Radiated Fields and Conducted Current Leakage from the Pulsed Power Systems in the National Ignition Facility at LLNL

Description: An important pulsed power system consideration is that they inherently generate fields and currents that can cause interference in other subsystems and diagnostics. Good pulsed power design, grounding and isolation practices can help mitigate these unwanted signals. During the laser commissioning shots for the NIF Early Light milestone at LLNL, measurements were made of the radiated field and conducted currents caused by the Power Conditioning System (PCS) modules with flash lamp load and the Plasma Electrode Pockels Cell (PEPC) driver. The measurements were made in the capacitor bay, laser bay, control room and target bay. The field measurements were made with B-dot and E-dot probes with bandwidth of about 100MHz. The current measurements were made with a clamp on probe with a bandwidth of about 20 MHz. The results of these measurements show fields and currents in the NIF Facility well below that required for interference with other subsystems. Currents on the target chamber from the pulsed power systems are well below the background noise currents.
Date: July 31, 2003
Creator: Anderson, R. A.; Clancy, T. J.; Fulkerson, S.; Petersen, D.; Pendelton, D.; Hulsey, S. et al.
Partner: UNT Libraries Government Documents Department
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