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Tactical Vulnerability Assessment Training Program (open access)

Tactical Vulnerability Assessment Training Program

The Department of Energy sponsors a 9-day training program for individual who are responsible for evaluating and planning safeguards systems and for preparing DOE Master and Security Agreements (MSSAs). These agreements between DOE headquarters and operations offices establish required levels of protection. The curriculum includes: (1) the nature of potential insider and outsider threats involving theft or diversion of special nuclear material, (2) use of computerized tools for evaluating the effectiveness of physical protection and material control and acoountability systems, and (3) methods for analyzing the benefits and costs of safeguards improvements and for setting priorities among proposed upgrades. The training program is varied and highly interactive. Presentations are intermixed with class discussions and ''hands-on'' analysis using computer tools. At the end of the program, participants demonstrate what they have learned in a two-and-one-half day ''field excercise,'' which is conducted on a facility scale-model. The training programs has been conducted six times and has been attended by representatives of all DOE facilities. Additional sessions are planned at four-month intervals. This paper describes the training program, use of the tools in preparing MSSAs for various DOE sites, and recent extensions and refinements of the evaluation tools.
Date: July 10, 1987
Creator: Al-Ayat, R. A.; Judd, B. R.; Renis, T. A.; Paulus, W. K.; Winblad, A. E. & Graves, B. R.
System: The UNT Digital Library
J/psi and UPSILON radiative and hadronic decays (open access)

J/psi and UPSILON radiative and hadronic decays

The search for gluonium at the J/psi and UPSILON is discussed, as well as the search for exotics at the UPSILON. Reactions discussed include radiative and hadronic decays of the J/psi and the search for radiative decays of the UPSILON. Future perspectives are also briefly considered. 45 refs., 27 figs. (LEW)
Date: July 1, 1987
Creator: Bloom, E. D.
System: The UNT Digital Library
MGA2 (Multiple Group Analysis): A one-detector code for rapid high-precision plutonium isotopic measurements (open access)

MGA2 (Multiple Group Analysis): A one-detector code for rapid high-precision plutonium isotopic measurements

The MGA (Multiple Group Analysis) code which we developed several years ago required two detectors when analyzing high SU Pu content samples. The isotopic information, which was obtained from the 300-keV regions, can now be obtained equally well from the low-energy region (50 to 208 keV). This breakthrough was achieved by developing a unique and highly accurate method for delineating the overall ''intrinsic'' efficiency curve, including the plutonium K-shell absorption edge discontinuity. Consequently, the intense 129- and 148-keV peak intensities can now be used reliably in place of the peaks in the 300-keV regions to determine the relative abundances of STZPu and SU Pu. The 203/208- and 148/152-keV pairs, and all of the intense 94- to 104-keV peaks, are included in the analysis to provide accurate data for the other isotopes of interest.
Date: July 1, 1987
Creator: Gunnink, R.
System: The UNT Digital Library
Fission barriers of hot rotating nuclei: Theoretical predictions and experimental tests (open access)

Fission barriers of hot rotating nuclei: Theoretical predictions and experimental tests

Recent theoretical developments in calculating fission barriers of hot rotating nuclei and their experimental tests are reviewed. The discussions are limited to macroscopic fission models (no shell effects), since experimental tests come primarily from heavy-ion induced reactions involving large angular momenta and internal excitation energies. The physics of the rotating finite range models with temperature is emphasized and the predictions of our model are compared with those of other macroscopic models and with statistically deduced experimental results. The difficulties associated with the statistical model analysis at high temperatures are discussed. 43 refs., 8 figs., 1 tab.
Date: July 7, 1987
Creator: Mustafa, M.G.
System: The UNT Digital Library
Validating safeguards effectiveness given inherently limited test data (open access)

Validating safeguards effectiveness given inherently limited test data

A key issue in designing and evaluating nuclear safeguards systems is how to validate safeguards effectiveness against a spectrum of potential threats. Safeguards effectiveness is measured by a performance indicator such as the probability of defeating an adversary attempting a malevolent act. Effectiveness validation means a testing program that provides sufficient evidence that the performance indicator is at an acceptable level. Traditional statistical techniques are useful in designing a testing program when numerous independent system trials are possible. However, within the safeguards environment, many situations arise for which traditional statistical approaches may be neither feasible nor appropriate. Such situations can occur, for example, when there are obvious constraints on the number of possible tests due to operational impacts and testing costs. Furthermore, these tests are usually simulations (e.g., staged force-on-force exercises) rather than actual tests, and the system is often modified after each test. Under such circumstances, it is difficult to make and justify inferences about system performance by using traditional statistical techniques. In this paper, we discuss several alternative quantitative techniques for validating system effectiveness. The techniques include: (1) minimizing the number of required tests using sequential testing; (2) combining data from models inspections and exercises using Bayesian statistics …
Date: July 10, 1987
Creator: Sicherman, A.
System: The UNT Digital Library
Determination of UTW K/sub XSi/ factors for low atomic number microanalysis: A systematic approach (open access)

Determination of UTW K/sub XSi/ factors for low atomic number microanalysis: A systematic approach

A systematic measurement of experimental K/sub XSi/ factors, with particular emphasis on low Z microanalysis (6 less than or equal to 7 less than or equal to 32), at 200 kV for a KEVEX UTW Si(Li) detector fitted to a JEOL 200CX analytical microscope, using a variety of high purity standards has been carried out. Under normal operating conditions of a LaB/sub 6/ filament, it is shown that absorption in the specimen is very critical, particularly for heavy element matrices, and sample thicknesses need to be measured for accurate microanalysis of low Z elements (C,N,O). Using these measured K/sub XSi/ factors, quantitative UTW-EDX microanalysis has been routinely extended to carbon. 21 refs.
Date: July 1, 1987
Creator: Krishnan, K.M. & Echer, C.J.
System: The UNT Digital Library
Chemical equilibrium calculations for the high pressure and temperature dissociation of liquid nitrogen (open access)

Chemical equilibrium calculations for the high pressure and temperature dissociation of liquid nitrogen

Calculations are reported for the equation-of-state properties of shock-compressed liquid nitrogen. The statistical mechanical, chemical equilibrium calculations, which allow for the simultaneous presence of both the diatomic and monatomic forms of nitrogen, show good agreement with recent dynamic experiments.
Date: July 1, 1987
Creator: Hamilton, D. C. & Ree, F. H.
System: The UNT Digital Library
Measurements of electron excitation and recombination for Ne-like Ba/sup 46 +/ (open access)

Measurements of electron excitation and recombination for Ne-like Ba/sup 46 +/

A new facility at Lawrence Livermore National Laboratory has been used to obtain measurements for electron-impact excitation, dielectronic recombination and radiative recombination for the neon-like Ba/sup 46 +/ ion. The experimental technique consists of trapping highly charged ions inside the space charge of an electron beam and measuring their x-ray emission spectra.
Date: July 1, 1987
Creator: Marrs, R. E.; Levine, M. A.; Knapp, D. A. & Henderson, J. R.
System: The UNT Digital Library
High average power linear induction accelerator development (open access)

High average power linear induction accelerator development

There is increasing interest in linear induction accelerators (LIAs) for applications including free electron lasers, high power microwave generators and other types of radiation sources. Lawrence Livermore National Laboratory has developed LIA technology in combination with magnetic pulse compression techniques to achieve very impressive performance levels. In this paper we will briefly discuss the LIA concept and describe our development program. Our goals are to improve the reliability and reduce the cost of LIA systems. An accelerator is presently under construction to demonstrate these improvements at an energy of 1.6 MeV in 2 kA, 65 ns beam pulses at an average beam power of approximately 30 kW. The unique features of this system are a low cost accelerator design and an SCR-switched, magnetically compressed, pulse power system. 4 refs., 7 figs.
Date: July 1, 1987
Creator: Bayless, J.R. & Adler, R.J.
System: The UNT Digital Library
Progress in High-Resolution X-Ray Holographic Microscopy (open access)

Progress in High-Resolution X-Ray Holographic Microscopy

Among the various types of x-ray microscopes that have been demonstrated, the holographic microscope has had the largest gap between promise and performance. The difficulties of fabricating x-ray optical elements have led some to view holography as the most attractive method for obtaining the ultimate in high resolution x-ray micrographs; however, we know of no investigations prior to 1987 that clearly demonstrated submicron resolution in reconstructed images. Previous efforts suffered from problems such as limited resolution and dynamic range in the recording media, low coherent x-ray flux, and aberrations and diffraction limits in visible light reconstruction. We have addressed the recording limitations through the use of an undulator x-ray source and high-resolution photoresist recording media. For improved results in the readout and reconstruction steps, we have employed metal shadowing and transmission electron microscopy, along with numerical reconstruction techniques. We believe that this approach will allow holography to emerge as a practical method of high-resolution x-ray microscopy. 30 refs., 4 figs.
Date: July 1, 1987
Creator: Jacobsen, Chris; Kirz, J.; Howells, Malcolm; McQuaid, Kenneth; Rothman, Stephen; Feder, Ralph et al.
System: The UNT Digital Library
Nitrogen at very high pressure (open access)

Nitrogen at very high pressure

High-pressure results for nitrogen are reviewed and discussed in terms of phenomena that occur at extreme conditions.
Date: July 1, 1987
Creator: Nellis, W.J.
System: The UNT Digital Library
Electrical Conductivity and Equation of State Measurements on Planetary Fluids at High Pressures and Temperatures (open access)

Electrical Conductivity and Equation of State Measurements on Planetary Fluids at High Pressures and Temperatures

Hugoniot equation-of-state, shock temperature, and electrical conductivity measurements are reported for fluids believed to be the primary constituents of the planets Uranus and Neptune. The equation-of-state results are compared with calculations performed using a statistical mechanical, chemical equilibrium computer code and electrical conductivities are discussed in terms of the recently measured magnetic field of Uranus. 4 refs., 2 figs., 1 tab.
Date: July 1, 1987
Creator: Hamilton, D. C.; Nellis, W. J.; Holmes, N. C.; Radousky, H. B.; Ree, F. H. & Nicol, M.
System: The UNT Digital Library
Safety and licensing of MHTGR (Modular High Temperature Gas Cooled Reactor) (open access)

Safety and licensing of MHTGR (Modular High Temperature Gas Cooled Reactor)

The Modular High Temperature Gas Cooled Reactor (MHTGR) design meets stringent top-level regulatory and user safety requirements that require that the normal and off-normal operation of the plant not disturb the public's day-to-day activities. Quantitative, top-level regulatory criteria have been specified from US NRC and EPA sources to guide the design. The user/utility group has further specified that these criteria be met at the plant boundary. The focus of the safety approach has then been centered on retaining the radionuclide inventory within the fuel by removing core heat, controlling chemical attack, and by controlling heat generation. The MHTGR is shown to passively meet the stringent requirements with margin. No operator action is required and the plant is insensitive to operator error.
Date: July 1, 1987
Creator: Silady, F.A.; Millunzi, A.C.; Kelley, A.P. Jr. & Cunliffe, J.
System: The UNT Digital Library
Theoretical approaches to chemical dynamics in highly compressed fluids (open access)

Theoretical approaches to chemical dynamics in highly compressed fluids

Methods that have been developed in the chemical physics community over the previous decade are applied to problems involving the dynamic chemical behavior of fluids under highly compressed conditions. The methods require detailed structural information about the environment seen by the reacting molecules. These methods are briefly reviewed. Examples for both statically compressed and shock conditions are discussed.
Date: July 1, 1987
Creator: Calef, D.F.
System: The UNT Digital Library
The SLAC Linear Collider: A status report (open access)

The SLAC Linear Collider: A status report

This report presents progress made at the Stanford Linear Collider (SLC). Design goals of the various components are compared to measurements made on the equipment. 8 figs., 2 tabs. (JDH)
Date: July 1, 1987
Creator: Richter, B. & Stiening, R.
System: The UNT Digital Library
Modes, masses, metallicities, and magnitudes of RR Lyrae variables (open access)

Modes, masses, metallicities, and magnitudes of RR Lyrae variables

The author reviews past and recent developments in the study of RR Lyrae variables. He provides supporting evidence for a large helium content but remains uncertain as to their masses and luminosities. Time dependent convection is offered as a probable explanation for the double mode pulsations of these stars. 25 refs., 8 figs., 3 tabs.
Date: July 1, 1987
Creator: Cox, A. N.
System: The UNT Digital Library
Industrial applications of ion implantation into metal surfaces (open access)

Industrial applications of ion implantation into metal surfaces

The modern materials processing technique, ion implantation, has intriguing and attractive features that stimulate the imaginations of scientists and technologists. Success of the technique for introducing dopants into semiconductors has resulted in a stable and growing infrastructure of capital equipment and skills for use of the technique in the economy. Attention has turned to possible use of ion implantation for modification of nearly all surface related properties of materials - optical, chemical and corrosive, tribological, and several others. This presentation provides an introduction to fundamental aspects of equipment, technique, and materials science of ion implantation. Practical and economic factors pertaining to the technology are discussed. Applications and potential applications are surveyed. There are already available a number of ion-implanted products, including ball-and-roller bearings and races, punches-and-dies, injection screws for plastics molding, etc., of potential interest to the machine tool industry.
Date: July 1, 1987
Creator: Williams, J. M.
System: The UNT Digital Library
Properties of e/sup +/e/sup -/ interactions at. sqrt. s = 50 and 52 GeV (open access)

Properties of e/sup +/e/sup -/ interactions at. sqrt. s = 50 and 52 GeV

Bhabha scattering and multi-hadronic e/sup +/e/sup -/ annihilation events have been observed in the AMY detector at ..sqrt..s = 50 GeV and ..sqrt..s = 52 GeV at the TRISTAN e/sup +/e/sup -/ storage ring. Here we report the results of a preliminary analysis of the properties of these events. We present results for the e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/, e/sup +/e/sup -/ ..-->.. ..gamma gamma.. and e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/ differential cross sections as well as for R, the ratio of e/sup +/e/sup -/ annihilation into hadrons to that for dimuons. In addition we present results on the characteristics of the final state hadrons in the annihilation events.
Date: July 1, 1987
Creator: unknown
System: The UNT Digital Library
EXELFS (Extended Electron Energy Loss Fine Structure) of amorphous and crystalline SiC. [Extended Electron Energy Loss Fine Structure] (open access)

EXELFS (Extended Electron Energy Loss Fine Structure) of amorphous and crystalline SiC. [Extended Electron Energy Loss Fine Structure]

Extended Electron Energy Loss Fine Structure (EXELFS) is a technique which is sensitive to the local atomic environment surrounding atoms. The ability to perform EXELFS measurements with the use of an electron microscope enables one to study materials properties at high spatial resolution. Its use as a method to evaluate amorphous materials is especially noteworthy since EXELFS is sensitive to the structure and composition within near neighbor distances of specific types of atoms. The materials used in this study included single crystal SiC, single crystal SiC made amorphous by ion implantation with chromium, and single crystal SiC made amorphous under a converged 300 kV electron beam. EXELFS results, based upon the Si K edge, exhibit significant differences for crystalline SiC versus the SiC made amorphous by ion implantation. The position of peaks in the radial distribution function (RDF), representing the Si-C and the Si-Si interatomic bonds, indicate an expansion in the nearest neighbor distances for the ion implanted amorphous SiC. Also the Si-Si/Si-C peak intensity ratio for the amorphous material was significantly lower than that for crystalline SiC. These results imply that the tetrahedral (Si-C) bonds are retained to a greater degree than the longer Si-Si bonds. A loss in …
Date: July 1, 1987
Creator: Angelini, P.; Sevely, J. C.; Hssein, K. & Zanchi, G.
System: The UNT Digital Library
The Mark III vertex chamber and prototype test results (open access)

The Mark III vertex chamber and prototype test results

A vertex chamber has been constructed for use in the Mark III experiment. The chamber is positioned inside the current main drift chamber and will be used to trigger data collection, to aid in vertex reconstruction, and to improve the momentum resolution. This paper discusses the chamber's construction and performance and tests of the prototype.
Date: July 1, 1987
Creator: Grab, C.
System: The UNT Digital Library
Experimental review of light quark spectroscopy from e/sup +/e/sup -/ production and. gamma gamma. collisions (open access)

Experimental review of light quark spectroscopy from e/sup +/e/sup -/ production and. gamma gamma. collisions

This is an experimental review of light quark spectroscopy from e/sup +/e/sup -/ production and ..gamma gamma.. collision results presented at the 2nd International Conference on Hadron Spectroscopy at KEK, Japan. The recent results in ..gamma gamma.. production have evidence for the J/sup PC/ = 1/sup + +/, E/f/sub 1/(1420) and D/f/sub 1/(1285), mesons from the TPC and Mark II collaborations and upper limits for pseudoscalar resonances from the Crystal Ball collaboration. The results in J/psi reactions include D/f/sub 1/(1285) meson production in radiative decays and a complete measurement of the hadronic decays into pseudoscalar-vector pairs from the DM2 collaboration and evidence for phi phi production in radiative decays and a study of the iota line shape from the Mark III collaboration. A short review of simple theoretical ideas is presented.
Date: July 1, 1987
Creator: Toki, W.H.
System: The UNT Digital Library
Limits on rare D-meson decays (open access)

Limits on rare D-meson decays

The latest results from a number of experiments on searches for rare decays of the charmed D-mesons are summarized. This talk reports on upper limits on flavor changing weak neutral current reactions and on processes that do not conserve the lepton family number.
Date: July 1, 1987
Creator: Grab, C.
System: The UNT Digital Library
Influence of internally generated fields on odd-photon pumping of dipole-allowed transitions in atomic gases (open access)

Influence of internally generated fields on odd-photon pumping of dipole-allowed transitions in atomic gases

The dramatic influence of multiwave mixing processes on resonant multiphoton excitation of dipole-allowed quantum transitions are discussed. Brief comparisons are made between different theoretical approaches used in treating the same underlying physics, and between the predictions and available experimental manifestations of the phenomenon for three-photon and five-photon induced processes.
Date: July 1, 1987
Creator: Garrett, W. R.
System: The UNT Digital Library
Gravity and fault structures, Long Valley caldera, California (open access)

Gravity and fault structures, Long Valley caldera, California

The main and catastrophic phase of eruption in Long Valley occurred 0.73 m.y. ago with the eruption of over 600 km/sup 3/ of rhyolitic magma. Subsequent collapse of the roof rocks produced a caldera which is now elliptical in shape, 32 km east-west by 17 km north-south. The caldera, like other large Quarternary silicic ash-flow volcanoes that have been studied by various workers, has a nearly coincident Bouguer gravity low. Earlier interpretations of the gravity anomaly have attributed the entire anomaly to lower density rocks filling the collapsed structure. However, on the basis of many additional gravity stations and supporting subsurface data from several new holes, a much more complex and accurate picture has emerged of caldera structure. From a three-dimensional inversion of the residual Bouguer gravity data we can resolve discontinuities that seem to correlate with extensions of pre-caldera faults into the caldera and faults associated with the ring fracture. Some of these faults are believed related to the present-day hydrothermal upflow zone and the zone of youngest volcanic activity within the caldera.
Date: July 1, 1987
Creator: Carle, S. F. & Goldstein, N. E.
System: The UNT Digital Library