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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

Description: This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Las… more
Date: September 1, 1991
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.
Partner: UNT Libraries Government Documents Department
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Numerical simulation of a short RFQ resonator using the MAFIA codes

Description: The electrical characteristics of a short (2{beta}{lambda}=0.4 m) resonator with large modulation (m=4) have been studied using the three dimensional codes, MAFIA. The complete resonator, including the modulated electrodes and a complex support structure, has been simulated using {approximately} 350,000 mesh points. Important characteristics studied include the resonant frequency, electric and magnetic fields distributions, quality factor and stored energy. The results of the numerical simulati… more
Date: January 1, 1991
Creator: Wang, H.; Ben-Zvi, Ilan; Jain, A.; Paul, P. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics) & Lombardi, A. (Istituto Nazionale di Fisica Nucleare, Legnaro (Italy). Lab. Nazionale di Legnaro)
Partner: UNT Libraries Government Documents Department
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INEX simulations of the optical performance of the AFEL

Description: The AFEL (Advanced Free-Electron Laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high-brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf-linac. Initial laser experiments will be performed with a 1-cm-period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 {mu}m. Future experiments will operate with slotted-tube'' electromagnetic wiggle… more
Date: January 1, 1991
Creator: Goldstein, J.C.; Wang, T.S.F. & Sheffield, R.L.
Partner: UNT Libraries Government Documents Department
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DWPF waste glass Product Composition Control System

Description: The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canist… more
Date: January 1, 1992
Creator: Brown, K.G. & Postles, R.L.
Partner: UNT Libraries Government Documents Department
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Decommissioning of a grout- and waste-filled storage tank in the 200 East Area of the Hanford Site

Description: A self-concentrating waste tank located at the Strontium Semiworks Facility in the 200 East Area of the Hanford Site will be decommissioned following waste removal. During a previous decommissioning phase, the tank, thought to be empty, was filled with grout to prevent it from collapsing over time. Several years later, an agitator rod was pulled from within the tank and found to contain significant amounts of radiation, indicating there was still radioactive waste in the tank. Several alternati… more
Date: January 1, 1991
Creator: Marske, S.G.
Partner: UNT Libraries Government Documents Department
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Reviews of ASME Section 11 pump and valve relief requests: Post Generic Letter 89-04

Description: This paper presents a discussion of ASME Section 11 Pump and Valve Inservice Testing relief request reviews by the NRC and their contractors. Topics that will be discussed include the scope of USNRC reviews in Technical Evaluation Reports (TERs) (and Safety Evaluation, SEs); including the basis for granting relief requests, the status of relief requests in IST Program updates, and the Generic Letter 89-04 approval process; and the level of technical detail required in submitted programs. This p… more
Date: January 1, 1992
Creator: DiBiasio, A.
Partner: UNT Libraries Government Documents Department
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Prospects of physics at CDF with the SVX

Description: During next physics run CDF will strongly enhance its heavy flavor tagging capabilities with the installation of a silicon vertex detector (SVX), that will allow precise measurements of secondary decay vertices in the plane transverse to the beam (impact parameter resolution {approx equal} 12 {mu}m). We expect this detector to have a significant impact on b-physics (c{tau}{sub B} {approx equal} 350 {mu}m) and top search. In the following we will discuss CDF prospects for top search and for CP v… more
Date: September 1, 1991
Creator: Dell'Agnello, S.
Partner: UNT Libraries Government Documents Department
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Design and performance of liquid hydrogen target systems for the Fermilab Fixed Target Program

Description: The Fermilab 1990--1991 Fixed Target Program featured six experiments utilizing liquid hydrogen or liquid deuterium targets as part of their apparatus. Each design was optimized to the criteria of the experiment, resulting in variations of material selection, methods of refrigeration and secondary containment. Collectively, the targets were run for a total of 14,184 hours with an average operational efficiency of 97.6%. The safe and reliable operation of these targets was complemented by an inc… more
Date: July 1, 1991
Creator: Allspah, D.; Danes, J.; Peifer, J. & Stanek, R.
Partner: UNT Libraries Government Documents Department
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Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds

Description: The formation and radiative properties of clouds are poorly parameterized in numerical climate models, especially marine boundary layer clouds. Twomey (1991), after describing the importance of cloud microphysics to the climate problem, states Clearly, many more field measurements and laboratory experiments are called for, rather than endless repetitions of computer simulations that are closely related to each other and parameterize in very similar ways.'' The effort described here is a field e… more
Date: January 1, 1991
Creator: Porch, W.; Buchwald, M.; Glatzmaier, T.; Kao, C.-Y.; Unruh, W. (Los Alamos National Lab., NM (United States)); Hudson, J. et al.
Partner: UNT Libraries Government Documents Department
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The limited streamer tubes system for the SLD warm iron calorimeter

Description: The SLD detector at the Stanford Linear Accelerator Center is a general purpose device for studying e{sup +}{epsilon}{sup {minus}} interaction at the Z{sup 0}. The SLD calorimeter system consists of two parts: a lead Liquid Argon Calorimeter (LAC) with both electromagnetic (22 radiation lengths) and hadronic sections (2.8 absorption lengths) housed inside the coil, and the Warm Ion limited streamer tubes Calorimeter (WIC) outside the coil which uses as radiator the iron of the flux return for t… more
Date: January 1, 1992
Creator: Benvenuti, A. C.; Camanzi, B.; Piemontese, L.; Zucchelli, P.; Calcaterra, A.; De Sangro, R. et al.
Partner: UNT Libraries Government Documents Department
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Non-linear instability of DIII-D to error fields

Description: Otherwise stable DIII-D discharges can become nonlinearly unstable to locked modes and disrupt when subjected to resonant m = 2, n = 1 error field caused by irregular poloidal field coils, i.e. intrinsic field errors. Instability is observed in DIII-D when the magnitude of the radial component of the m = 2, n = 1 error field with respect to the toroidal field is B{sub r21}/B{sub T} of about 1.7 {times} 10{sup {minus}4}. The locked modes triggered by an external error field are aligned with the … more
Date: October 1, 1991
Creator: La Haye, R. J. & Scoville, J. T.
Partner: UNT Libraries Government Documents Department
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Measurements of Non-Leptonic Weak Decays of Lambda Hypernuclei

Description: Aspects of recent measurements of the mesonic and non-mesonic partial decay rates of {sub {Lambda}}{sup 5}He, and {sub {Lambda}}{sup 12}C are discussed. We comment on what the experiments tell us about the spin-isospin structure of {Delta}S=1 weak interaction in the nuclear environment. 14 refs., 1 fig.
Date: January 1, 1991
Creator: Schumacher, Reinhard A.
Partner: UNT Libraries Government Documents Department
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Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

Description: The objective of this work is to develop a regenerable activated-bauxite sorber alkali monitor that requires no high-temperature/high-pressure sampling line for the reliable in situ measurement of alkali-vapor concentration in the exhaust from the pressurized fluidized-bed combustion of coal. 11 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Lee, S. H. D. & Swift, M. W.
Partner: UNT Libraries Government Documents Department
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Resource capture by single leaves

Description: Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfull… more
Date: May 1, 1992
Creator: Long, S.P.
Partner: UNT Libraries Government Documents Department
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Lost circulation technology development status

Description: Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50% through the development of mitigation and characteri… more
Date: January 1, 1992
Creator: Glowka, D. A.; Schafer, D. M.; Loeppke, G. E.; Scott, D. D.; Wernig, M. D. & Wright, E. K.
Partner: UNT Libraries Government Documents Department
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Potential for use of high-temperature superconductors in fusion reactors

Description: The present rate of development of high-temperature superconductors (HTSs) is sufficiently rapid that there may be opportunities for their use in contemporary fusion devices such as the International Thermonuclear Experimental Reactor (ITER). The most likely 1application is for delivering power to the superconducting magnets, especially in substituting for the current leads between the temperatures of 4 K and 77K. A second possible application of HTSs is as a liquid-nitrogen-cooled power bus, c… more
Date: January 1, 1991
Creator: Hull, J.R.
Partner: UNT Libraries Government Documents Department
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Power excitation by the use of a rf wiggler

Description: It is well-known that there are difficulties to obtain rf power sources of significant amount for frequencies larger than 3 GHz. Yet, rf sources in the centimeter/millimeter wavelength range would be very useful to drive, for example, high-gradient accelerating linacs for electron-positron linear colliders. We would like to propose an alternative method to produce such radiation. It makes use of a short electron bunch traveling along the axis of a waveguide which is at the same time excited by … more
Date: January 1, 1992
Creator: Ruggiero, Alessandro G.
Partner: UNT Libraries Government Documents Department
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Development of a low intensity current monitor system

Description: This report documents the development of a current transformer system used to measure pulsed ion beam currents with a wide dynamic intensity range (nA to mA, and factor of 10{sup 6}). Peak beam currents at the LAMPF accelerator typically range from 100 to nA to 40 mA with pulse widths varying from 30 to 1000 {mu}s. Signal conditioning of the peak current output provides an average current readout with a range of 1 nA to 2 mA, noise of approximately {plus minus}0.5 nA, and accuracy of {plus minu… more
Date: January 1, 1991
Creator: Gallegos, F.R.
Partner: UNT Libraries Government Documents Department
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Estimates of SASE power in the short wavelength region

Description: Given a sufficiently bright electron beam, the self-amplified-spontaneous emission (SASE) can provide gigawatts of short wavelength coherent radiation. The advantages of SASE approach are that is requires neither optical cavity nor an imput seed laser. In this note, we estimate the peak power performance of SASE for wavelengths shorter than 1000 {Angstrom}. At each wavelength, we calculate the saturated power from a uniform parameter undulator and the enhanced power from a tapered undulator. Th… more
Date: March 1, 1992
Creator: Kim, Kwang-Je.
Partner: UNT Libraries Government Documents Department
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Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

Description: We have used a bioenergetically-driven, individual-based model (IBM) of striped bass as a framework for synthesizing available information on population biology and quantifying, in a relative sense, factors that potentially affect year class success. The IBM has been configured to simulate environmental conditions experienced by several striped bass populations; i.e., in the Potomac River, MD; in Hudson River, NY; in the Santee-Cooper River System, SC, and; in the San Joaquin-Sacramento River S… more
Date: January 1, 1991
Creator: Cowan, J.H., Jr. (Maryland Univ., Solomons, MD (United States). Chesapeake Biological Lab.) & Rose, K.A. (Oak Ridge National Lab., TN (United States))
Partner: UNT Libraries Government Documents Department
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CW 100MW microwave power transfer in space

Description: A proposal is made for high-power microwave transfer in space. The concept consists in a microwave power station integrating a multistage microwave free-electron laser and asymmetric dual-reflector system. Its use in space is discussed. 9 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Takayama, K. (Houston Univ., TX (United States). Inst. for Beam Particle Dynamics National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan) Texas Accelerator Center, The Woodlands, TX (United States)); Hiramatsu, S. (National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)) & Shiho, M. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan))
Partner: UNT Libraries Government Documents Department
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Optical design and performance of the X25 hybrid wiggler beam line at the NSLS

Description: The X25 beam line at the National Synchrotron Light Source (NSLS) began full-power commissioning in 1990. It extracts radiation from a 27 pole hybrid wiggler, which produces up to 1.8 kW of total power with a peak horizontal density of 450 W/mrad and critical energy of 4.6 keV. The design and performance of the beam line optics are described, in particular the cooling of the first monochromator crystal. 28 refs., 5 figs.
Date: January 1, 1991
Creator: Berman, L. E.; Hastings, J. B.; Oversluizen, T. & Woodle, M.
Partner: UNT Libraries Government Documents Department
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Design and operation of an inert gas facility for thermoelectric generator storage

Description: While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen perm… more
Date: January 1, 1990
Creator: Goebel, C. J.
Partner: UNT Libraries Government Documents Department
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