Magnetic core studies at LBNL and LLNL (open access)

Magnetic core studies at LBNL and LLNL

The objective of this work is to minimize the cost of the materials and maximize the performance of magnetic cores, a major cost component of a Heavy-Ion-Fusion, HIF, induction accelerator driver. This includes selection of the alloy for cost and performance, and maximizing the performance of each alloy evaluated. The two major performance parameters are the magnetic flux swing and the energy loss. The volt seconds of the cores, obtained from the flux swing with Faraday's Law, determines the beam energy and duration. Core losses from forming domains and moving their boundaries are a major factor in determining the efficiency of an induction accelerator.
Date: September 20, 1997
Creator: Molvik, A.W.; Faltens, A.; Reginato, L.; Blaszkiewicz, M.; Smith, C. & Wood, R.
System: The UNT Digital Library
Direct conversion of spent fuel to High-Level-Waste (HLW) glass (open access)

Direct conversion of spent fuel to High-Level-Waste (HLW) glass

The Glass Material Oxidation and Dissolution System (GMODS) is a recently invented process for the direct, single-step conversion of spent nuclear fuel (SNF) to high-level waste (HLW) glass. GMODS converts metals, ceramics, organics, and amorphous solids to glass in a single step. Conventional vitrification technology can not accept feeds containing metals or carbon. The GMODS has the potential to solve several issues associated with the disposal of various US Department of Energy (DOE) miscellaneous SNFs: (1) chemical forms unacceptable for repository disposal; (2) high cost of qualifying small quantities of particular SNFs for disposal; (3) limitations imposed by high-enriched SNF in a repository because of criticality and safeguards issues; and (4) classified design information. Conversion of such SNFs to glass eliminates these concerns. A description of the GMODS, {open_quotes}strawman{close_quotes} product criteria, experimental work to date, and product characteristics are included herein.
Date: September 20, 1994
Creator: Forsberg, C. W.; Beahm, E. C.; Parker, G. W. & Rudolph, J.
System: The UNT Digital Library
Recent developments in cabling technology used to manufacture superconducting accelerator magnets (open access)

Recent developments in cabling technology used to manufacture superconducting accelerator magnets

The cable is the heart of superconducting accelerator magnets. Since the initial development of the Rutherford cable, more than twenty years ago, many improvements in manufacturing techniques have increased the current carrying capacity. An experimental cabling machine was designed and constructed at LBL in 1984.
Date: September 20, 1993
Creator: Royet, J. & Scanlan, R. M.
System: The UNT Digital Library
Recycling technologies and market opportunities: Proceedings (open access)

Recycling technologies and market opportunities: Proceedings

These proceedings are the result of our collective effort to meet that challenge. They reflect the dedication and commitment of many people in government, academia, the private sector and national laboratories to finding practical solutions to one of the most pressing problems of our time -- how to deal effectively with the growing waste s that is the product of our affluent industrial society. The Conference was successful in providing a clear picture of the scope of the problem and of the great potential that recycling holds for enhancing economic development while at the same time, having a significant positive impact on the waste management problem. That success was due in large measure to the enthusiastic response of our panelists to our invitation to participate and share their expertise with us.
Date: September 20, 1993
Creator: Goland, A. N. & Petrakis, L.
System: The UNT Digital Library
CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD (open access)

CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD

The ATLAS Electromagnetic (EM) calorimeter (EMCAL) Front End Board (FEB) will be located in custom-designed enclosures solidly connected to the feedtroughs. It is a complex mixed signal board which includes the preamplifier, shaper, switched capacitor array analog memory unit (SCA), analog to digital conversion, serialization of the data and related control logic. It will be described in detail elsewhere in these proceedings. The electromagnetic interference (either pick-up from the on board digital activity, from power supply ripple or from external sources) which affects coherently large groups of channels (coherent noise) is of particular concern in calorimetry and it has been studied in detail.
Date: September 20, 1999
Creator: CHASE,B. CITTERIO,M. LANNI,F. MAKOWIECKI,D. RADEKA,S. RESCIA,S. TAKAI,H. ET AL.
System: The UNT Digital Library
The ramp rate dependence of the sextupole field in superconducting dipoles (open access)

The ramp rate dependence of the sextupole field in superconducting dipoles

Sextupole components are induced in the magnetic field of superconducting dipoles when the current is changed. The magnitude of this effect depends on the rate of change of field, the strand-to-strand resistance in the superconducting cable, and the twist pitch of the wire. Ramp rate measurements have been made on a number of SSC dipoles wound from conductors with different interstrand resistances. The technique employed uses an array of Hall probes sensitive to the sextupole field and can measure the difference for field increasing or decreasing as a function of axial position. Magnets with very low interstrand resistance exhibit a large axial oscillation in the sextupole field between up and down ramps which is rate dependent When the strand resistance is high the amplitude of this oscillation is almost independent of ramp rate.
Date: September 20, 1993
Creator: Ghosh, A. K.; Robins, K. E. & Sampson, W. B.
System: The UNT Digital Library
Strongly driven ion acoustic waves in laser produced plasmas (open access)

Strongly driven ion acoustic waves in laser produced plasmas

This paper present an experimental study of ion acoustic waves with wavenumbers corresponding to stimulated Brillouin scattering. Time resolved Thomson scattering in frequency and wavenumber space, has permitted to observe the dispersion relation of the waves as a function of the laser intensity. Apart from observing ion acoustic waves associated with a strong second component is observed at laser intensities above 10{sup 13}Wcm{sup {minus}2}.
Date: September 20, 1994
Creator: Baldis, H. A.; Labaune, C. & Renard, N.
System: The UNT Digital Library
Numerical Modeling of Coupled Variably-Saturated Fluid Flow and Reactive Transport with Fast and Slow Chemical Reactions (open access)

Numerical Modeling of Coupled Variably-Saturated Fluid Flow and Reactive Transport with Fast and Slow Chemical Reactions

The couplings among chemical reaction rates, advective and diffusive transport in fractured media or soils, and changes in hydraulic properties due to precipitation and dissolution within fractures and in rock matrix are important for both nuclear waste disposal and remediation of contaminated sites. This paper describes the development and application of LEHGC2.0, a mechanistically-based numerical model for simulation of coupled fluid flow and reactive chemical transport including both fast and slow reactions invariably saturated media. Theoretical bases and numerical implementations are summarized, and two example problems are demonstrated. The first example deals with the effect of precipitation-dissolution on fluid flow and matrix diffusion in a two-dimensional fractured media. Because of the precipitation and decreased diffusion of solute from the fracture into the matrix, retardation in the fractured medium is not as large as the case wherein interactions between chemical reactions and transport are not considered. The second example focuses on a complicated but realistic advective-dispersive-reactive transport problem. This example exemplifies the need for innovative numerical algorithms to solve problems involving stiff geochemical reactions.
Date: September 20, 1999
Creator: LI, MING-HSU; SIEGEL, MALCOLM D. & YEH, GOUR-TSYH (GEORGE)
System: The UNT Digital Library
Bipolaron Hopping Conduction in Boron Carbides (open access)

Bipolaron Hopping Conduction in Boron Carbides

The electrical conductivities of boron carbides, B{sub 12+x}C{sub 3{minus}x} with 0.1 < x < 1.7, between 300 and 1200K suggest the hopping of a nearly temperature-independent density of small (bi)polarons. The activation energies of the nobilities are low, {approx} 0.16 eV, and are nearly independent of the composition. At lower temperatures, conductivities have non-Arrhenius temperature dependencies and strong sensitivity to carbon concentration. Percolative aspects of low-temperature hopping are evident in this sensitivity to composition. Boron carbides' Seebeck coefficients are anomalous in that (1) they are much larger than expected from boron carbides' large carrier densities and (2) they depend only weakly on the carrier density. Carrier-induced softening of local vibrations gives contributions to the Seebeck coefficient that mirror the magnitudes and temperature dependencies found in boron carbides.
Date: September 20, 1999
Creator: ASELAGE, TERRENCE L.; EMIN, D. & MCCREADY, STEVEN S.
System: The UNT Digital Library
BAR-CODE BASED WEIGHT MEASUREMENT STATION FOR PHYSICAL INVENTORY TAKING OF PLUTONIUM OXIDE CONTAINERS AT THE MINING AND CHEMICAL COMBINE RADIOCHEMICAL REPROCESSING PLANT NEAR KRASNOYARSK, SIBERIA. (open access)

BAR-CODE BASED WEIGHT MEASUREMENT STATION FOR PHYSICAL INVENTORY TAKING OF PLUTONIUM OXIDE CONTAINERS AT THE MINING AND CHEMICAL COMBINE RADIOCHEMICAL REPROCESSING PLANT NEAR KRASNOYARSK, SIBERIA.

This paper describes the technical tasks being implemented to computerize the physical inventory taking (PIT) at the Mining and Chemical Combine (Gorno-Khimichesky Kombinat, GKhK) radiochemical plant under the US/Russian cooperative nuclear material protection, control, and accounting (MPC and A) program. Under the MPC and A program, Lab-to-Lab task agreements with GKhK were negotiated that involved computerized equipment for item verification and confirmatory measurement of the Pu containers. Tasks under Phase I cover the work for demonstrating the plan and procedures for carrying out the comparison of the Pu container identification on the container with the computerized inventory records. In addition to the records validation, the verification procedures include the application of bar codes and bar coded TIDs to the Pu containers. Phase II involves the verification of the Pu content. A plan and procedures are being written for carrying out confirmatory measurements on the Pu containers.
Date: September 20, 1999
Creator: Suda, S.
System: The UNT Digital Library
Upgrade of the Nuclear Material Protection, Control and Accounting System at the VNIIEF Industrial Zone (open access)

Upgrade of the Nuclear Material Protection, Control and Accounting System at the VNIIEF Industrial Zone

The Industrial Zone at the Russian Federal Nuclear Center/All-Russian Scientific Research Institute of Experimental Physics (RFNC/VNEEF) consists of ten guarded areas with twenty two material balance areas (A and As). The type of facilities in the Industrial Zone include storage sites, machine shops, research facilities, and training facilities. Modernization of the Material Protection, Control and Accounting (MPC and A) System at the Industrial Zone started in 1997. This paper provides a description of, the methodology/strategy used in the upgrade of the MFC and A system.
Date: September 20, 1999
Creator: Lewis, J.C.; Maltsev, V. & Singh, S.P.
System: The UNT Digital Library
Finite Element Modeling of Micromachined MEMS Photon Devices (open access)

Finite Element Modeling of Micromachined MEMS Photon Devices

The technology of microelectronics that has evolved over the past half century is one of great power and sophistication and can now be extended to many applications (MEMS and MOEMS) other than electronics. An interesting application of MEMS quantum devices is the detection of electromagnetic radiation. The operation principle of MEMS quantum devices is based on the photoinduced stress in semiconductors, and the photon detection results from the measurement of the photoinduced bending. These devices can be described as micromechanical photon detectors. In this work, we have developed a technique for simulating electronic stresses using finite element analysis. We have used our technique to model the response of micromechanical photon devices to external stimuli and compared these results with experimental data. Material properties, geometry, and bimaterial design play an important role in the performance of micromechanical photon detectors. We have modeled these effects using finite element analysis and included the effects of bimaterial thickness coating, effective length of the device, width, and thickness.
Date: September 20, 1999
Creator: Datskos, P. G.; Evans, B. M. & Schonberger, D.
System: The UNT Digital Library
A fiber optics sensor for strain and stress management in superconducting accelerator magnets (open access)

A fiber optics sensor for strain and stress management in superconducting accelerator magnets

A novel cryogenic interferometric fiber optics sensor for the measurement of strain and stress in the coil windings of superconducting accelerator magnets is described. The sensor can operate with two different readout sources, monochromatic laser light and white light respectively. The sensor head is built up as an extrinsic Fabry-Perot interferometer formed with two cleaved fiber surfaces, and can be mounted in several configurations. When read with laser light, the sensor is an extremely sensitive relative strain or temperature detector. When read with white light the absolute strain and pressure can be measured. Results are presented of tests in several configurations at 77 K and 4.2 K, both for the relative and absolute readout method. Finally, the possible use for quench localization using the temperature sensitivity is described.
Date: September 20, 1993
Creator: van Oort, J. M. & ten Kate, H. H. J.
System: The UNT Digital Library
Nonlinearity with disorder: Spatio-temporal complex behavior arising from length scales competition (open access)

Nonlinearity with disorder: Spatio-temporal complex behavior arising from length scales competition

One of the many mechanisms underlying complex behavior in physical systems is competition between different length or time scales, which may arise naturally in the considered system or may be imposed by external influences. The purpose of this paper is the following. By means of three examples the authors will illustrate how identification of relevant length scales can lead to a separation of the system behavior in two regimes. Far from the competition region, it can be described in very simple ways, usually involving a few degrees of freedom. On the contrary, when relevant scales are in conflict, the behavior of the system turns out to be complex, typically chaotic. Therefore, the success of this approach is that it goes straightforwardly to the deep reasons for complex behavior, making amenable to analytical studies all other regimes.
Date: September 20, 1993
Creator: Sanchez, A. & Bishop, A. R.
System: The UNT Digital Library
Evaluation of APC NbTi superconductor in a model dipole magnet (open access)

Evaluation of APC NbTi superconductor in a model dipole magnet

The artificial pinning center (APC) approach to NbTi superconductor fabrication offers the potential benefits of higher current density and lower cost than the conventional process for NbTi. We have been evaluating several approaches for fabricating NbTi via the APC approach to determine whether these advantages can be realized in a practical conductor. The study began with the fabrication by several vendors of 10kg size samples which were evaluated as short samples. This was followed by the scale-up of one process to 150mm diameter billets. This material was evaluated first in a solenoid configuration and recently in a one-meter long dipole. We will report here on the results of these coil tests and other characterization results for this new material. We will also describe the plans to continue the scale-up to full size billets and we will discuss the potential cost savings of this approach compared with conventional NbTi fabrication.
Date: September 20, 1993
Creator: Scanlan, R. M.; Lietzke, A.; Royet, J.; Wandesforde, A.; Taylor, C. E.; Wong, J. et al.
System: The UNT Digital Library
Fabrication of sub-40-nm p-n junctions for 0.18 {mu}m MOS device applications using a cluster-tool-compatible, nanosecond thermal doping technique (open access)

Fabrication of sub-40-nm p-n junctions for 0.18 {mu}m MOS device applications using a cluster-tool-compatible, nanosecond thermal doping technique

In this paper, we introduced an alternative deep-submicrometer doping technology, Projection Gas Immersion Laser Doping (P-GILD). Representing the marriage of lithography and diffusion, P-GILD is a resistless, step-and-repeat doping process that utilizes excimer laser light patterned by a dielectric reticle to selectively heat and, thereby, dope regions of an integrated circuit. Results of physical and electrical characterization are presented for ultra-shallow p{sup +} {minus}n and n{sup +} {minus}p junctions produced by gas immersion laser doping (GILD), a phenomenologically identical technique that utilizes an aluminum contact mask rather than a dielectric reticle to pattern the beam. Junctions produced using GILD exhibit uniformly-doped, abrupt impurity profiles with no apparent defect formation in the silicon. Electrically, sheet and contact resistivities of the ultra-shallow junctions are less than 100{Omega}/sheet and 1 {times} 10{sup {minus}6} {Omega}{sm_bullet}cm{sup 2}, respectively, while n{sup +} {minus}p and p{sup +} {minus}n diodes exhibit nearly ideal forward bias behavior and reverse leakage current densities less than 5 nA/cm{sup 2} at {minus}5V. Uniformity of both diode characteristics and sheet resistance for junctions produced by the step-and-repeat process is also shown to be better than {plus_minus}5% across a 4-inch wafer.
Date: September 20, 1993
Creator: Weiner, K. H. & McCarthy, A. M.
System: The UNT Digital Library
Systematics of hadronic production from Si and Pb with 14.6 {times} A GeV/c Si beams (open access)

Systematics of hadronic production from Si and Pb with 14.6 {times} A GeV/c Si beams

The differential cross sections for production of K{sub s}{sup 0}`s, {Lambda}`s and {pi}{sup {minus}}`s from Si and Pb targets using 14.6 {times} A GeV/c Si beams at the AGS are presented as a function of rapidity and transverse mass. These results are compared with model predictions and K{sub s}{sup 0} production is compared with {pi}{sup {minus}} production.
Date: September 20, 1993
Creator: Saulys, A. C. & Collaboration, E810
System: The UNT Digital Library
The Spallation Neutron Source Accumulator Ring (open access)

The Spallation Neutron Source Accumulator Ring

The Spallation Neutron Source Accumulator ring is described. Also described are the challenging accelerator physics problems associated with space charge issues, injection, extraction, and beam loss.
Date: September 20, 1998
Creator: Lee, Y. Y.
System: The UNT Digital Library
BIOCHEMICAL PROCESSES FOR GEOTHERMAL BRINE TREATMENT (open access)

BIOCHEMICAL PROCESSES FOR GEOTHERMAL BRINE TREATMENT

As part of the DOE Geothermal Energy Program, BNL's Advanced Biochemical Processes for Geothermal Brines (ABPGB) project is aimed at the development of cost-efficient and environmentally acceptable technologies for the disposal of geothermal wastes. Extensive chemical studies of high and low salinity brines and precipitates have indicated that in addition to trace quantities of regulated substances, e.g., toxic metals such as arsenic and mercury, there are significant concentrations of valuable metals, including gold, silver and platinum. Further chemical and physical studies of the silica product have also shown that the produced silica is a valuable material with commercial potential. A combined biochemical and chemical technology is being developed which (1) solubilizes, separates, and removes environmentally regulated constituents in geothermal precipitates and brines (2) generates an amorphous silica product which may be used as feedstock for the production of revenue generating materials, (3) recover economically valuable trace metals and salts. Geothermal power resources which utilize low salinity brines and use the Stretford process for hydrogen sulfide abatement generate a contaminated sulfur cake. Combined technology converts such sulfur to a commercial grade sulfur, suitable for agricultural use. The R and D activities at BNL are conducted jointly with industrial parties in an …
Date: September 20, 1998
Creator: Premusic, E. T.; Lin, M. S.; Bohenek, M.; Joshi-Top, G.; Zhou, W.; Shelenkova, L. et al.
System: The UNT Digital Library
Computational Methods for Sensitivity and Uncertainty Analysis in Criticality Safety (open access)

Computational Methods for Sensitivity and Uncertainty Analysis in Criticality Safety

Interest in the sensitivity methods that were developed and widely used in the 1970s (the FORSS methodology at ORNL among others) has increased recently as a result of potential use in the area of criticality safety data validation procedures to define computational bias, uncertainties and area(s) of applicability. Functional forms of the resulting sensitivity coefficients can be used as formal parameters in the determination of applicability of benchmark experiments to their corresponding industrial application areas. In order for these techniques to be generally useful to the criticality safety practitioner, the procedures governing their use had to be updated and simplified. This paper will describe the resulting sensitivity analysis tools that have been generated for potential use by the criticality safety community.
Date: September 20, 1999
Creator: Broadhead, B. L.; Childs, R. L. & Rearden, B. T.
System: The UNT Digital Library
Proposed Methodology for Establishing Area of Applicability (open access)

Proposed Methodology for Establishing Area of Applicability

This paper presents the application of sensitivity and uncertainty (S/U) analysis methodologies to the data validation tasks of a criticality safety computational study. The S/U methods presented are designed to provide a formal means of establishing the area (or range) of applicability for criticality safety data validation studies. The development of parameters that are analogous to the standard trending parameters form the key to the technique. These parameters are the so-called D parameters, which represent the differences by energy group of S/U-generated sensitivity profiles, and c parameters, which are the k correlation coefficients, each of which give information relative to the similarity between pairs of selected systems. The use of a Generalized Linear Least-Squares Methodology (GLLSM) tool is also described in this paper. These methods and guidelines are also applied to a sample validation for uranium systems with enrichments greater than 5 wt %.
Date: September 20, 1999
Creator: Broadhead, B. L.; Hopper, C. M. & Parks, C. V.
System: The UNT Digital Library
Open charm production in deep inelastic scattering at next-to-leading order at HERA. (open access)

Open charm production in deep inelastic scattering at next-to-leading order at HERA.

An introduction and overview of charm production in deep inelastic scattering at HERA is given. The existing next-to-leading order perturbative QCD calculations are then reviewed, and key results are summarized. Finally, comparisons are made with the most recent HERA data, and unresolved issues are highlighted.
Date: September 20, 1999
Creator: Harris, B. W.
System: The UNT Digital Library
Analytical Benchmark Test Set for Criticality Code Verification (open access)

Analytical Benchmark Test Set for Criticality Code Verification

A number of published numerical solutions to analytic eigenvalue (k{sub eff}) and eigenfunction equations are summarized for the purpose of creating a criticality verification benchmark test set. The 75-problem test set allows the user to verify the correctness of a criticality code for infinite medium and simple geometries in one- and two-energy groups, one- and two-media, and both isotropic and linearly anisotropic neutron scattering. A three- and six-energy group infinite medium problem are also included in the test set. The problem specifications will produce both k{sub eff}=1 and the quoted k{sub {infinity}} to at least five decimal places. Additional uses of the test set for code verification are also discussed. Los Alamos report LA-13511 contains the details of all 75 test problems.
Date: September 20, 1999
Creator: Sood, A.; Forster, R. A. & Parson, D. K.
System: The UNT Digital Library
Impact of MCNP Unresolved Resonance Probability-Table Treatment on Uranium and Plutonium Benchmarks (open access)

Impact of MCNP Unresolved Resonance Probability-Table Treatment on Uranium and Plutonium Benchmarks

A probability-table treatment recently has been incorporated into an intermediate version of the MCNP Monte Carlo code named MCNP4XS. This paper presents MCNP4XS results for a variety of uranium and plutonium criticality benchmarks, calculated with and without the probability-table treatment. It is shown that the probability-table treatment can produce small but significant reactivity changes for plutonium and {sup 233}U systems with intermediate spectra. More importantly, it can produce substantial reactivity increases for systems with large amounts of {sup 238}U and intermediate spectra.
Date: September 20, 1999
Creator: Mosteller, R. D. & Little, R. C.
System: The UNT Digital Library