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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
Testing program for determining the mechanical properties of concrete to temperatures of 621/sup 0/C (open access)

Testing program for determining the mechanical properties of concrete to temperatures of 621/sup 0/C

Concrete temperatures in a Liquid Metal Fast Breeder Reactor (LMFBR) in excess of normal code limits can result from postulated large sodium spills in equipment cells. Elevated temperature concrete property data which may have application for providing a basis for the design and evaluation of such postulated accident conditions is limited. Data thus needed to be developed commensurate with LMFBR plant applications for critical physical and mechanical concrete properties under prototypic thermal accident conditions. A test program was conducted to define the variations in physical and mechanical properties of a limestone aggregate concrete and a lightweight insulating concrete exposed to elevated temperatures. Five test series were conducted: unconfined compression, shear, rebar bond, sustained loading (creep), and thermal properties. Testing procedures for determining the mechanical properties of concrete from ambient to 621/sup 0/C (1150/sup 0/F) are described. Ther thermal properties tests are discussed in a separate paper which is also being presented at this conference.
Date: January 1, 1980
Creator: Oland, C.B.; Naus, D.J. & Robinson, G.C.
System: The UNT Digital Library
Neutron environment in d + Li facilities (open access)

Neutron environment in d + Li facilities

A microscopic d + Li neutron yield model has been developed based upon classical models and experimental data. Using equations suggested by the Serber and evaporation models, a generalized least squares adjustment procedure generated angular yields for E/sub d/ to 40 MeV using the available experimental data. The HEDL-UCD experiment at E/sub d/ = 35 was used to adjust parameters describing the neutron spectra. The model is used to predict yields, spectra, and damage responses in the FMIT Test Cell.
Date: January 1, 1980
Creator: Mann, F. M.; Schmittroth, F. & Carter, L. L.
System: The UNT Digital Library
Cryogenic supplies for the TFTR neutral beam line cryopanels (open access)

Cryogenic supplies for the TFTR neutral beam line cryopanels

Cryocondensing panels will be used for the Neutral Beam Lines of the TFTR to satisfy a pumping speed requirement of 2.5 x 10/sup 6/ l/s. The cryocondensing panels are fed by liquid helium (LHe), boiling at selectable temperatures of 4.5/sup 0/K or 3.8/sup 0/K. Liquid nitrogen (LN/sub 2/) panels and chevrons thermally shield the LHe panel. The closed-loop LHe supply system and the open loop LN/sub 2/ system are discussed. The helium refrigerator of minimum 1070-W capacity, together with its distribution system, and the nitrogen distribution system in the ton/hour LN/sub 2/ range is presented. Problems and their solutions in connection with the LHe system, including the distribution over a distance of 500 feet of large quantities of liquid/gas mixtures with load variations over the range of about 3 : 1, and the economies of various types of distribution lines (passive, pumped, shielded, combined), are described. The system design passed the preliminary phase. Design features and auxiliary equipment to assure dispersion of large quantities of nitrogen into the atmosphere and to permit operation under degraded cryogenic helium refrigerator performance are also discussed in Design Considerations.
Date: January 1, 1977
Creator: Pinter, G.
System: The UNT Digital Library
Potential energy for quarks (open access)

Potential energy for quarks

It is argued on theoretical and phenomenological grounds that confinement of quarks is intrinsically a many-body interaction. The Born-Oppenheimer approximation to the bag model is shown to give rise to a static potential energy that consists of a sum of two-body Coulomb terms and a many-body confining term. Following the success of this potential in heavy Q anti Q systems it is being applied to Q/sup 2/ anti Q/sup 2/. Preliminary calculations suggest that dimeson bound states with exotic flavor, such as bb anti s anti s, exist. 13 refs., 5 figs.
Date: January 1, 1985
Creator: Heller, L.
System: The UNT Digital Library
Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements (open access)

Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements

A number of fuel cycles have been proposed for evaluation in the nonproliferation alternative systems assessment program. Among these systems are light water reactors (LWR) operating on the thorium-uranium cycle or the plutonium-thorium cycle either inside or outside energy centers. These proposals support the President's nuclear power policy of accelerating research into alternative fuel cycles that do not permit direct access to materials usable for nuclear weapons but still retain the benefits of nuclear power. Reprocessing and refabrication (often referred to as the ''back cycle'') constitute a portion of the overall fuel cycle and represent potential access points to fissionable materials, which, in many cases, may be in a rather attractive form for diversion. These operations for LWR thorium-uranium and plutonium-thorium fuels were analyzed to assess and rate the diversion or proliferation potential of each major operation. Reprocessing and refabrication evaluations per se constitute insufficient data for rating the acceptability of an entire fuel cycle and must be considered along with reactor analysis, environmental data, resource utilization, and political factors. Each back cycle operation has been evaluated according to needed development, material location, material description, convertibility and radiation hazard. Needed development relates to the state of the art of the …
Date: January 1, 1978
Creator: Carter, W. L.; Rainey, R. H. & Johnson, D. R.
System: The UNT Digital Library
First order study for an iron core OH system for TNS (open access)

First order study for an iron core OH system for TNS

A simple comparison has been made between an air core and an iron core ohmic heating system for a particular device, and it was shown that the peak power requirements can be substantially reduced by the use of an iron core to power levels handled by industry today. It was also shown that for an ohmic heating system initiated plasma that the cost of the iron core ohmic heating power system (iron core, dual rectifier, and DC switch) is less than the cost for a subset of the power system for an air core system (dual rectifier and DC switch). There is considerable work being done on other methods of initiating the plasma none of which seem to be incompatible with the use of an iron core system.
Date: January 1, 1977
Creator: Ballou, J. K. & Schultz, J.
System: The UNT Digital Library
Evaluation of ISABELLE full cell ultra high vacuum system (open access)

Evaluation of ISABELLE full cell ultra high vacuum system

The ISABELLE Full Cell Vacuum System consisting of a 40 m long, by 8.8 cm diameter stainless steel tube pumped by seven pumping stations was assembled and processed for 10/sup -12/ Torr operation. Evaluation and testing of the system and its sub-assemblies has been completed. Detail design of system components and the determination of the conditioning process was completed. The best procedure to rough pump, leak test, vacuum bake the system, condition pumps, degas gauges, turn on ion pumps and flash sublimation pumps was established. Pressures below 2 x 10/sup -11/ Torr are now routinely achieved in normal operation of the Full Cell. This includes pump down after replacement of various components and pump down after back fill with moist unfiltered air. The techniques developed for the Full Cell will be used to build the ISABELLE Ultra High Vacuum System.
Date: January 1, 1980
Creator: Foerster, C L; Briggs, J; Chou, T S & Stattel, P
System: The UNT Digital Library
Experimental program to validate analyses of accelerator breeder concepts (open access)

Experimental program to validate analyses of accelerator breeder concepts

The concept of using high-energy particle accelerators to produce neutrons for converting fertile material to fissile is over 25 years old. It is only relatively recently that accelerator design has progressed to a point where the operation approaches commercial viability. Critical unknowns in the concept were identified in a detailed study of specic configurations. Experiments to elucidate these unknowns in a timely manner using existing material and facilities are defined and identified. Basic measurements are described to evaluate effects of the primary particle beam and resulting secondary particles in massive assemblies of most materials of interest.
Date: January 1, 1977
Creator: Talbert Jr., W. L.; Russell, G. J. & Malenfant, R. E.
System: The UNT Digital Library
Generation of coherent soft x-rays using a single-pass free-electron laser amplifier (open access)

Generation of coherent soft x-rays using a single-pass free-electron laser amplifier

We consider a single-pass free-electron laser (FEL) amplifier, driven by an rf-linac followed by a damping ring for reduced emittance, for use in generating coherent light in the soft x-ray region. The dependence of the optical gain on electron-beam quality, studied with the three-dimensional FEL simulation code FELEX, is given and related to the expected power of self-amplified spontaneous emission. We discuss issues for the damping ring designed to achieve the required electron beam quality. The idea of a multipass regenerative amplifier is also presented. 6 refs., 3 tabs.
Date: January 1, 1987
Creator: Wang, T. F.; Goldstein, J. C.; Newmam, B. E. & McVey, B. D.
System: The UNT Digital Library
Selective population of high-j states via heavy-ion-induced transfer reactions (open access)

Selective population of high-j states via heavy-ion-induced transfer reactions

One of the early hopes of heavy-ion-induced transfer reactions was to populate states not seen easily or at all by other means. To date, however, I believe it is fair to say that spectroscopic studies of previously unknown states have had, at best, limited success. Despite the early demonstration of selectivity with cluster transfer to high-lying states in light nuclei, the study of heavy-ion-induced transfer reactions has emphasized the reaction mechanism. The value of using two of these reactions for spectroscopy of high spin states is demonstrated: /sup 143/Nd(/sup 16/O,/sup 15/O) /sup 144/Nd and /sup 170/Er(/sup 16/O,/sup 15/O..gamma..) /sup 171/Er. (WHK)
Date: January 1, 1982
Creator: Bond, P.D.
System: The UNT Digital Library
SIMMER as a safety analysis tool (open access)

SIMMER as a safety analysis tool

SIMMER has been used for numerous applications in fast reactor safety, encompassing both accident and experiment analysis. Recent analyses of transition-phase behavior in potential core disruptive accidents have integrated SIMMER testing with the accident analysis. Results of both the accident analysis and the verification effort are presented as a comprehensive safety analysis program.
Date: January 1, 1982
Creator: Smith, L. L.; Bell, C. R.; Bohl, W. R.; Bott, T. F.; Dearing, J. F. & Luck, L. B.
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
Characterization of low-level waste from the industrial sector, and near-term projection of waste volumes and types (open access)

Characterization of low-level waste from the industrial sector, and near-term projection of waste volumes and types

A telephone survey of low-level waste generators has been carried out in order to make useful estimates of the volume and nature of the waste which the generators will be shipping for disposal when the compacts and states begin operating new disposal facilities. Emphasis of the survey was on the industrial sector, since there has been little information available on characteristics of industrial LLW. Ten large industrial generators shipping to Richland, ten shipping to Barnwell, and two whose wastes had previously been characterized by BNL were contacted. The waste volume shipped by these generators accounted for about two-thirds to three-quarters of the total industrial volume. Results are given in terms of the categories of LLW represented and of the chemical characteristics of the different wastes. Estimates by the respondents of their near-term waste volume projections are presented.
Date: January 1, 1988
Creator: MacKenzie, D.R.
System: The UNT Digital Library
Conductor qualification tests for the 30-MJ Bonneville Power Administration SMES coil (open access)

Conductor qualification tests for the 30-MJ Bonneville Power Administration SMES coil

The 30-MJ energy storage coil for the Bonneville Power Administration requires a low-loss, cryostable conductor that is able to carry 4.9 kA in a field of 2.8 T and will maintain its properties over 10/sup 8/ partial discharge cycles. The multi-level cable which satisfies these requirements has been extensively tested at various stages in its development and in its final form. Tests have been performed to determine the effect of manufacturing options on ac losses, low temperature electrical resistivity, stability, and fatigue resistance of the insulated conductor. This paper will concentrate on the stability and fatigue tests which have not previously been reported.
Date: January 1, 1980
Creator: Schermer, R. I.; Boenig, H. J.; Henke, M.; Turner, R. D. & Schramm, R.
System: The UNT Digital Library
A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system (open access)

A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system

The lack of suitable benchmark problems makes it difficult to test sensitivity codes with a covariance library. A benchmark problem has therefore been defined for one- and two-dimensional sensitivity and uncertainity analysis codes and code systems. The problem, representative of a fusion reactor blanket, has a simple, three-zone )tau)-z geometry containing a D-T fusion neutron source distributed in a central void region surrounded by a thick /sup 6/LiH annulus. The response of interest is the /sup 6/Li tritium production per source neutron, T/sub 6/. The calculation has been performed with SENSIBL using other codes from the AARE code system as a test of both SENSIBL and the linked, modular system. The caluclation was performed using the code system in the standard manner with a covariance data library in the COVFILS-2 format but modified to contain specifically tailored covariance data for H and /sup 6/Li (Path A). The calculation was also performed by a second method which uses specially perturbed H and Li cross sections (Path B). This method bypasses SENSIBL and allows a hand calculation of the benchmark T/sub 6/ uncertainties. The results of Path A and Path B were total uncertainties in T/sub 6/ of 0.21% and 0.19%, respectively. …
Date: January 1, 1988
Creator: Muir, D. W.; Davidson, J. W.; Dudziak, D. J.; Davierwalla, D. M.; Higgs, C. E. & Stepanek, J.
System: The UNT Digital Library
Recovery of plutonium and americium from chloride salt wastes by solvent extraction (open access)

Recovery of plutonium and americium from chloride salt wastes by solvent extraction

Plutonium and americium can be recovered from aqueous waste solutions containing a mixture of HCl and chloride salt wastes by the coupling of two solvent extraction systems: tributyl phosphate (TBP) in tetrachloroethylene (TCE) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in TCE. In the flowsheet developed, the salt wastes are dissolved in HCl, the Pu(III) is oxidized to the IV state with NaClO/sub 2/ and recovered in the TBP-TCE cycle, and the Am is then removed from the resultant raffinate by the CMPO-TCE cycle. The consequences of the feed solution composition and extraction behavior of these species on the process flowsheet design, the Pu-product purity, and the decontamination of the aqueous raffinate from transuranic elements are discussed. 16 refs., 6 figs.
Date: January 1, 1987
Creator: Reichley-Yinger, L. & Vandegrift, G.F.
System: The UNT Digital Library
Data analysis and management for the Uranium Resource Evaluation Project (open access)

Data analysis and management for the Uranium Resource Evaluation Project

The Department of Energy has funded a large data collection effort with the purpose of determining the US uranium resources. This Uranium Resource Evaluation (URE) Project required a large data management effort which involved collection, retrieval, processing, display, and analysis of large volumes of data. Many of the characteristics of this data processing system are relevant to other applications, particularly where routine processing involves analyses for input into numerous technical reports. The URE Project computing system has a modular program structure which has enabled a straightforward interface with both special and general graphics and analysis packages such as SAS, BMDP, and SURFACE II. Other topics include cost-effective computing, data quality, report quality computer output, and test versus production program development.
Date: January 1, 1980
Creator: Kane, V.E.
System: The UNT Digital Library
Source-jerk analysis using a semi-explicit inverse kinetic technique (open access)

Source-jerk analysis using a semi-explicit inverse kinetic technique

A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means of measuring k in systems that are close to critical (i.e., 0.95 < k < 1.0). As a system becomes more subcritical (i.e., k << 1.0) spatial effects can introduce significant biases depending on the source and detector positions. However, methods are available that can correct for these biases and, hence, can allow measuring subcriticality in systems with k as low as 0.5. 12 refs., 3 figs.
Date: January 1, 1985
Creator: Spriggs, G.D. & Pederson, R.A.
System: The UNT Digital Library
Operating experience and procedures at the tritium systems test assembly (open access)

Operating experience and procedures at the tritium systems test assembly

Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig.
Date: January 1, 1988
Creator: Carlson, R.V.; Binning, K.E.; Cole, S. P.; Jenkins, E. M.; Wilhelm, R. C. & Cole, S. P.
System: The UNT Digital Library
Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho (open access)

Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho

Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydrothermal system of higher temperature than the one now observed.
Date: January 1, 1982
Creator: Arney, B.
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
Calculations of thermal-reactor spent-fuel nuclide inventories and comparisons with measurements (open access)

Calculations of thermal-reactor spent-fuel nuclide inventories and comparisons with measurements

Comparisons with integral measurements have demonstrated the accuracy of CINDER codes and libraries in calculating aggregate fission-product properties, including neutron absorption, decay power, and decay spectra. CINDER calculations have, alternatively, been used to supplement measured integral data describing fission-product decay power and decay spectra. Because of the incorporation of the extensive actinide library and the use of ENDF/B-V data, it is desirable to compare the inventory of individual nuclides obtained from tandem EPRI-CELL/CINDER-2 calculations with those determined in documented benchmark inventory measurements of spent reactor fuel. The development of the popular /sup 148/Nd burnup measurement procedure is outlined, and areas of uncertainty in it and lack of clarity in its interpretation are indicated. Six inventory samples of varying quality and completeness are examined. The power histories used in the calculations have been listed for other users.
Date: January 1, 1982
Creator: Wilson, W. B.; LaBauve, R. J. & England, T. R.
System: The UNT Digital Library
Magma energy and geothermal permeability enhancement programs (open access)

Magma energy and geothermal permeability enhancement programs

Accomplishments during FY85 and project plans for FY86 are described for the Magma Energy Extraction and Permeability Enhancement programs. (ACR)
Date: January 1, 1985
Creator: Dunn, J.C.
System: The UNT Digital Library