Resource Type

Numerical simulation of a short RFQ resonator using the MAFIA codes (open access)

Numerical simulation of a short RFQ resonator using the MAFIA codes

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 simulations are compared with the measurements of an actual resonator and analytical approximations. 7 refs., 3 figs., 1 tab.
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)
System: The UNT Digital Library
INEX simulations of the optical performance of the AFEL (open access)

INEX simulations of the optical performance of the AFEL

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 wigglers (formerly called pulsed- wire'' wigglers). Experiments at both fundamental and higher-harmonic wavelengths are planned. This paper presents results of INEX (Integrated Numerical EXperiment) simulations of the optical performance of the AFEL. These simulations use the electron micropulse produced by the accelerator/beam transport code PARMELA in the 3-D FEL simulation code FELEX. 9 refs., 4 figs., 6 tabs.
Date: January 1, 1991
Creator: Goldstein, J.C.; Wang, T.S.F. & Sheffield, R.L.
System: The UNT Digital Library
DWPF waste glass Product Composition Control System (open access)

DWPF waste glass Product Composition Control System

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 canisters for cooling and, ultimately, shipment to and storage in a geologic repository. The Product Composition Control System (PCCS) is the system intended to ensure that the melt will be processible and that the glass wasteform will be acceptable. This document provides a description of this system.
Date: January 1, 1992
Creator: Brown, K.G. & Postles, R.L.
System: The UNT Digital Library
Decommissioning of a grout- and waste-filled storage tank in the 200 East Area of the Hanford Site (open access)

Decommissioning of a grout- and waste-filled storage tank in the 200 East Area of the Hanford Site

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 alternative waste-removal options have been researched and evaluated. It is concluded that before the waste is to be disposed, the grout must be removed. This paper addresses that effort.
Date: January 1, 1991
Creator: Marske, S.G.
System: The UNT Digital Library
Reviews of ASME Section 11 pump and valve relief requests: Post Generic Letter 89-04 (open access)

Reviews of ASME Section 11 pump and valve relief requests: Post Generic Letter 89-04

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 presentation is based on the experiences of Brookhaven National Laboratory in reviewing IST Programs for the Mechanical Engineering Branch of the US Nuclear Regulatory Commission.
Date: January 1, 1992
Creator: DiBiasio, A.
System: The UNT Digital Library
Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds (open access)

Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds

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 experimental effort supported by the Department of Energy under its Quantitative Links'' program. The project is called Ship-Trail Evolution Above High Updraft Naval Targets (SEAHUNT). The purpose of this study is to improve our understanding of the meteorological context in which ship trails and other perturbations to marine boundary layer clouds occur. 8 refs., 6 figs.
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.
System: The UNT Digital Library
The limited streamer tubes system for the SLD warm iron calorimeter (open access)

The limited streamer tubes system for the SLD warm iron calorimeter

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 the magnetic field. The WIC completes the measurement of the hadronic shower energy ({approximately}85% on average is contained in the LAC) and it provides identification and tracking for muons over 99% of the solid angle. In this note we report on the construction, test and commissioning of such a large system.
Date: January 1, 1992
Creator: Benvenuti, A. C.; Camanzi, B.; Piemontese, L.; Zucchelli, P.; Calcaterra, A.; De Sangro, R. et al.
System: The UNT Digital Library
Measurements of Non-Leptonic Weak Decays of Lambda Hypernuclei (open access)

Measurements of Non-Leptonic Weak Decays of Lambda Hypernuclei

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.
System: The UNT Digital Library
The microscopic world: A demonstration of electron microscopy for younger students (open access)

The microscopic world: A demonstration of electron microscopy for younger students

None
Date: January 1, 1991
Creator: Horton, L. L.
System: The UNT Digital Library
Alkali sorber (RABSAM), September 1, 1990--August 30, 1991 (open access)

Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

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.
System: The UNT Digital Library
Lost circulation technology development status (open access)

Lost circulation technology development status

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 characterization technology. This paper describes the technical progress made in this program during the period April 1991--March 1992. 8 refs.
Date: January 1, 1992
Creator: Glowka, D. A.; Schafer, D. M.; Loeppke, G. E.; Scott, D. D.; Wernig, M. D. & Wright, E. K.
System: The UNT Digital Library
Potential for use of high-temperature superconductors in fusion reactors (open access)

Potential for use of high-temperature superconductors in fusion reactors

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, connecting the power supplies to the magnets, thus reducing the ohmic heating losses over these relatively long cables. A third potential application of HTSs is as an inner high-field winding of the toroidal field coils that would operate at {approx}20 K. While the use of higher temperature magnets offers significant advantages to the reactor system, it is unlikely that tested conductors of this type will be available within the ITER time frame. 23 refs., 2 figs.
Date: January 1, 1991
Creator: Hull, J.R.
System: The UNT Digital Library
Power excitation by the use of a rf wiggler (open access)

Power excitation by the use of a rf wiggler

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 a TM propagating electromagnetic wave. It is well known that radiation can be obtained by wiggling the motion of the electrons in a direction perpendicular to the main one. The wiggling action can be included by electromagnetic fields in a fashion similar to the one caused by wiggler magnets. We found that an interesting mode of operation is to drive the waveguide with an excitation frequency very close to the cut off. For such excitation, the corresponding e.m. wave travels with a very large phase velocity which in turn has the effect to increase the wiggling action on the electron bunch. Our method, to be effective, relies also on the coherence of the radiation; that is the bunch length is taken …
Date: January 1, 1992
Creator: Ruggiero, Alessandro G.
System: The UNT Digital Library
Development of a low intensity current monitor system (open access)

Development of a low intensity current monitor system

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 minus}0.1%. Since the system has proved stable and highly reliable, calibration is performed yearly. The prototype unit was built in 1985 and the final production unit was completed in early 1989. 5 refs., 14 figs.
Date: January 1, 1991
Creator: Gallegos, F.R.
System: The UNT Digital Library
Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling (open access)

Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

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 System CA. These sites represent extremes in the geographic distribution and thus, environmental variability of striped bass spawning. At each location, data describing the physio-chemical and biological characteristics of the spawning population and nursery area are being collected and synthesized by means of a prioritized, directed field sampling program that is organized by the individual-based recruitment model. Here, we employ the striped bass IBM configured for the Potomac River, MD from spawning into the larval period to evaluate the potential for maternal contribution to affect larva survival and growth. Model simulations in which the size distribution and spawning day of females are altered indicate that larva survival is enhanced (3.3-fold increase) when a high fraction of females in the spawning population are large. Larva stage duration also is less …
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))
System: The UNT Digital Library
CW 100MW microwave power transfer in space (open access)

CW 100MW microwave power transfer in space

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))
System: The UNT Digital Library
Optical design and performance of the X25 hybrid wiggler beam line at the NSLS (open access)

Optical design and performance of the X25 hybrid wiggler beam line at the NSLS

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.
System: The UNT Digital Library
Design and operation of an inert gas facility for thermoelectric generator storage (open access)

Design and operation of an inert gas facility for thermoelectric generator storage

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 permitted to enter the devices will react with thermally hot components, preferentially with molybdenum in the insulating foils, and with graphites to form CO/CO{sub 2} gases which are corrosive to the thermopile. It was important therefore to minimize the amount of oxygen which could enter, by either limiting the effective in-leakage areas on the generators themselves, or by reducing the relative amount of oxygen within the environment around the generators, or both. With the generators already assembled and procedures in place to assure minimal in-leakage in handling, the approach of choice was to provide a storage environment which contains significantly less oxygen than normal air. 2 refs.
Date: January 1, 1990
Creator: Goebel, C. J.
System: The UNT Digital Library
Microwave separation of organic chemicals from mixed hazardous waste (open access)

Microwave separation of organic chemicals from mixed hazardous waste

The feasibility of utilizing the differential heating characteristics of microwave energy (MW) to aid in the chemical extraction and separation process of hazardous organic compounds from mixed hazardous waste, was studied at the INEL. The long-term objective of this work was to identify a practical method of separating or enhancing the separation process of organic hazardous waste components from mixed waste using microwave (MW) frequency radiation. Methods using MW energy for calcination, solidification, and drying of radioactive waste from nuclear facilities is becoming more attractive. In order to study the effectiveness of MW heating, samples of several organic chemicals simulating those which may be found at the Radioactive Waste Management Complex at the INEL were exposed to MW energy. Vapor collection and analysis was performed as a function of time, signal frequency, and MW power throughout the process. Signal frequencies ranging from 900 MHz t 8000 MHz were used. Although the signal frequency bandwidth of the selectivity was quite broad, for the material tested an indication of the frequency dependence in the selectivity of MW heating was given. Greater efficiency in terms of energy used and time required was observed. The relatively large electromagnetic field intensities generated at the resonant …
Date: January 1, 1992
Creator: Anderson, A. A. & Albano, R. K.
System: The UNT Digital Library
Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime (open access)

Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime

Exclusive measurements of charged products and neutrons were performed for the reactions {sup 197}Au + (29 MeV/u) {sup 208}Pb and {sup 209}Bi + (28.2 MeV/u) {sup 136}Xe. The multiplicities of neutrons and charged particles are found to indicate collision impact parameters with different sensitivities. Characteristic correlations observed between massive products and light particles suggest the dominance of the damped-reaction mechanism in the Fermi energy domain. For central collisions, massive fragments are no longer observed, and a considerable fraction of the mass of the system is found disassembled into light particles and clusters. 75 refs., 19 figs.
Date: January 1, 1991
Creator: Schroeder, W.U.
System: The UNT Digital Library
Vibration considerations in the design of the Advanced Photon Source at Argonne National Laboratory (open access)

Vibration considerations in the design of the Advanced Photon Source at Argonne National Laboratory

The Advanced Photon Source (APS), a new synchrotron radiation facility being built at Argonne National Laboratory, will provide the world's most brilliant X-ray beams for research in a wide range of technical fields. Successful operation of the APS requires an extremely stable positron closed orbit. Vibration of the storage ring quadrupole magnets, even in the submicron range, can lead to distortion of the positron closed orbit and to potentially unacceptable beam emittance growth, which results in degraded performance. This paper presents an overview of the technical approach used to minimize vibration response, beginning at the conceptual stage, through design and construction, and on to successful operation. Acceptance criteria relating to maximum allowable quadrupole magnet vibration are discussed. Soil properties are used to determine resonant frequencies of foundations and to predict attenuation characteristics. Two sources are considered to have the potential to excite the foundation: far-field sources, which are produced external to the facility, and near-field sources, which are produced within the facility. Measurements of ambient ground motion, monitored to determine far- field excitation, are presented. Ambient vibration was measured at several operating facilities within Argonne to gain insight on typical near-field excitation sources. Discussion covers the dynamic response characteristics of …
Date: January 1, 1991
Creator: Jendrzejczyk, J.A. & Wambsganss, M.W.
System: The UNT Digital Library
Aging Aircraft NDI Development and Demonstration Center (AANC): An overview (open access)

Aging Aircraft NDI Development and Demonstration Center (AANC): An overview

A major center with emphasis on validation of nondestructive inspection techniques for aging aircraft, the Aging Aircraft NDI Development and Demonstration Center (AANC), has been funded by the FAA at Sandia National Laboratories. The Center has been assigned specific tasks in developing techniques for the nondestructive inspection of static engine parts, assessing inspection reliability (POD experiments), developing test beds for nondestructive inspection validation, maintaining a FAA library of characterized aircraft structural test specimens, and leasing a hangar to house a high flight cycle transport aircraft for use as a full scale test bed. 3 refs.
Date: January 1, 1991
Creator: Walter, P. L.
System: The UNT Digital Library
Predicting aquatic macrophyte modeling of a new freshwater lake using remote sensing (open access)

Predicting aquatic macrophyte modeling of a new freshwater lake using remote sensing

Par Pond and L Lake are reservoirs on the Savannah River Site in South Carolina. Beds of aquatic macrophytes (primarily cattail and waterlilies) exist in Par Pond and are now beginning to develop in L Lake. Biophysical knowledge about Par Pond was used to develop environmental constraint criteria' to predict the future spatial distribution of aquatic macrophytes in L Lake. The L Lake biophysical data were placed in a 5 {times} 5 m raster geographic information system (GIS) and analyzed using Boolean logic. Areas in L Lake which were {le}4 m in depth, {le}10% slope, had a fetch of {le}500 m, and on suitable soil were identified. The final GIS model predicted the spatial distribution of 37.30 ha of aquatic macrophytes which met the environmental constraint criteria (cattails = 12.29 ha and waterlilies = 25.01 ha).
Date: January 1, 1992
Creator: Jensen, J. R.; Narumalani, S.; Weatherbee, O.; Morris, K. S., Jr. & Mackey, H. E., Jr.
System: The UNT Digital Library
Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion (open access)

Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion

Samples of the amino acid valine were irradiated by 2.5 MeV-Ar, 0.8 MeV-Kr and 1.0 MeV Xe beams from the Argonne Dynamitron accelerator in order to study the energy distributions of ejected secondary ions. For Kr and Xe the nuclear stopping power exceeded the electronic stopping power by a factor 2 or 3, respectively, but the functional shape of the energy distributions and the mean ejection energies (0.9--1.4 eV) indicated that the molecular ions (M{plus minus}H){sup {plus minus}} are desorbed by an electronic sputter process. Contributions of atomic collision cascades were observed for the H{sup {minus}} ion. In the second part of the article, the overall dependence of molecular ion yields on the electronic energy loss is discussed in the framework of recent desorption models and the structure of the nuclear track.
Date: January 1, 1991
Creator: Hunt, J.E. (Argonne National Lab., IL (United States)) & Wien, K. (Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik)
System: The UNT Digital Library