These notes present a brief survey of some of the current diagnostic techniques used in magnetic fusion plasma devices. To give an idea of the range of parameters and geometries encountered the parameters of four representative experiments - PLT, TMX, ZT-40 and EBT-I(S) - are given. The central issue of all experiments is to understand the flow of power which can be summarized by two volume integrated equations for the ions and electrons.

A report is given on progress made during the second year of a three year contract studying the feasibility of nuclear pumping the atomic iodine laser. Experimental results are presented showing efficiencies of 25--38% at converting neutron-induced nuclear reaction energy in the excimer XeBr into UV photons which can be used to pump the laser. Parametric studies were done utilizing the {sup 10}B(n,{alpha}){sup 7}Li reaction, with three bromine donor chemicals, over a range of pressures and mix ratios, to optimize the fluorescence efficiency.

The mechanical structure of the LLL/GA Mirror Hybrid Reactor vessel is briefly discussed. Functional requirements and over-all design considerations leading to selection of a post-tensioned concrete reactor vessel and a modular blanket approach are indicated. Module design life of four years, module replacement, capability and remote fueling are provided by the chosen structural design. (RME)

Laser-plasma instability experiments for laser fusion have followed three developments. These are advances in the technology and design of experiments, advances in diagnostics, and evolution of the design of high-gain targets. This paper traces the history of these three topics and discusses their present state. Today one is substantially able to produce controlled plasma conditions and to diagnose specific instabilities within such plasmas. Experiments today address issues that will matter for future laser facilities. Such facilities will irradiate targets with {approx}1 MJ of visible or UV light pulses that are tens of nanoseconds in duration, very likely with a high degree of spatial and temporal incoherence. 58 refs., 4 figs.

This paper presents a containment failure mode analysis during a spectrum of postulated degraded core accident sequences in a typical 1000-MW(e) boiling water reactor (BWR) with a Mark-I wetwell containment. Overtemperature failure of containment electric penetration assemblies (CEPAs) has been found to be the major failure mode during such accidents.

Optical ionization effects in gases appear to be very sensitive indicators of nonuniformities caused by contamination, deformation, and other factors affecting a metal surface. These optical effects are influenced by surface electron emission, which is influenced in turn by the chemical, metallurgical, and mechanical condition of the metal surface. Based on these effects, a general technique for inspection of critical parts that is fast, inexpensive, nondestructive, and not limited by size or geometry is presented. Ionization effects that reveal nonuniformities and were recorded with standard photographic equipment are shown.

This manual is intended to serve several purposes. The first goal is to describe the capabilities and operation of the SMC processor package from an operator or user point of view. Secondly, the manual will describe in some detail the basic hardware elements and how they can be used effectively to implement a step motor control system. Practical information on the use, installation and checkout of the hardware set is presented in the following sections along with programming suggestions. Available related system software is described in this manual for reference and as an aid in understanding the system architecture. Section two presents an overview and operations manual of the SMC processor describing its composition and functional capabilities. Section three contains hardware descriptions in some detail for the LLL-designed hardware used in the SMC processor. Basic theory of operation and important features are explained.

New switching power supplies were designed for the 10 mm laser amplifiers in the Nova Master Oscillator Room. The flashlamp supply must be repratable. Therefore, we designed a constant current, linearly charging power supply. Since it is a capacitor, the load varies throughout the charge cycle. At first the load is great, and di/dt of load current is at a maximum. As the capacitor charges the initial conditions for each cycle change, the power supply in effect sees a smaller capacitance, and di/dt decreases. We need a way of gradually increasing the on-time of the current pulses so that the transistors in the power bridge are turned off when they reach their maximum peak current. The normal current sense response of the control chip is not fast enough to be useful for our application. The deadtime, or the time that all the bridge transistors are turned off, is fixed so that as the pulse width varies so does the period. We end up with a constant peak current, switching power supply whose frequency varies from 50 khz to 20 khz. Finally, an overcurrent latch protects the transistors from bridge or transformer faults. The circuit is described and results are shown.

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also …

I will review the role that Monte Carlo methods play in the physical sciences. They are very widely used for a number of reasons: they permit the rapid and faithful transformation of a natural or model stochastic process into a computer code. They are powerful numerical methods for treating the many-dimensional problems that derive from important physical systems. Finally, many of the methods naturally permit the use of modern parallel computers in efficient ways. In the presentation, I will emphasize four aspects of the computations: whether or not the computation derives from a natural or model stochastic process; whether the system under study is highly idealized or realistic; whether the Monte Carlo methodology is straightforward or mathematically sophisticated; and finally, the scientific role of the computation.

We further investigate the dimensional duality (D-duality) proposed in arXiv: 0705.0550 by mainly focusing on the properties of D-branes in this background. We derive the world-sheet correspondence of static D-branes, and discuss the fate of non-static D-branes from the world-sheet viewpoint. The quantum string production with or without D-branes is also studied fromthe time-like Liouville theory. We find that the closed string production from the background is much larger than that from D-branes decaying into nothing.

Isopiestic vapor pressure measurements were made for {l_brace}yMgCl{sub 2} + (1-y)MgSO{sub 4}{r_brace}(aq) solutions with MgCl{sub 2} ionic strength fractions of y = 0, 0.1997, 0.3989, 0.5992, 0.8008, and (1) at the temperature 298.15 K, using KCl(aq) as the reference standard. These measurements for the mixtures cover the ionic strength range I = 0.9794 to 9.4318 mol {center_dot} kg{sup -1}. In addition, isopiestic measurements were made with NaCl(aq) as reference standard for mixtures of {l_brace}xNa{sub 2}SO{sub 4} + (1-x)MgSO{sub 4}{r_brace}(aq) with the molality fraction x = 0.50000 that correspond to solutions of the evaporite mineral bloedite (astrakanite), Na{sub 2}Mg(SO{sub 4}){sub 2} {center_dot} 4H{sub 2}O(cr). The total molalities, m{sub T} = m(Na{sub 2}SO{sub 4}) + m(MgSO{sub 4}), range from m{sub T} = 1.4479 to 4.4312 mol {center_dot} kg{sup -1} (I = 5.0677 to 15.509 mol {center_dot} kg{sup -1}), where the uppermost concentration is the highest oversaturation molality that could be achieved by isothermal evaporation of the solvent at 298.15 K. The parameters of an extended ion-interaction (Pitzer) model for MgCl2(aq) at 298.15 K, which were required for an analysis of the {l_brace}yMgCl{sub 2} + (1-y)MgSO{sub 4}{r_brace}(aq) mixture results, were evaluated up to I = 12.025 mol {center_dot} kg{sup -1} from published isopiestic …

Recent advances in the dust transport modeling in tokamak devices are discussed. Topics include: (1) physical model for dust transport; (2) modeling results on dynamics of dust particles in plasma; (3) conditions necessary for particle growth in plasma; (4) dust spreading over the tokamak; (5) density profiles for dust particles and impurity atoms associated with dust ablation in tokamak plasma; and (6) roles of dust in material/tritium migration.

The ultrafast dynamics of electronic excitations of the surface dangling bond states of Si(111) 7 x 7 has been investigated by second harmonic generation as a probe of transient spectral hole burning. Spectral holes induced by a 100 fs pump at {approx_equal} 1.5 eV and their decay are interpreted in terms of electronic dephasing times as short as 15 fs. This fast time scale together with the strong excitation-induced dephasing observed is interpreted in terms of carrier-carrier scattering. In addition, strong coupling of the electronic excitation to surface optical phonons is observed and attributed to the localization at adatom sites of a surface electronic excitation and a surface phonon mode.

This dissertation describes the measurement of the B{sup 0}{bar B}{sup 0} oscillation frequency {Delta}m{sub d} with a sample of 122 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at the Stanford Linear Accelerator Center. A fully inclusive approach is used to select dilepton events in which B meson decays semileptonically and the lepton's charge is employed to identify the flavor of each B meson. The oscillation frequency {Delta}m{sub d} is extracted from the time evolution of the dilepton events. A maximum likelihood fit to the same sign and opposite sign events simultaneously gives {Delta}m{sub d} = (0.485 {+-} 0.009(stat.) {+-} 0.010(syst.)) ps{sup 1} where the first uncertainty is statistical and the second is systematic. This is one of the single most precise measurements of the B{sup 0}{bar B}{sup 0} oscillation frequency to date.

Some gamma-ray burst (GRB) afterglow light curves show significant variability, which often includes episodes of rebrightening. Such temporal variability had been attributed in several cases to large fluctuations in the external density, or density ''bumps''. Here we carefully examine the effect of a sharp increase in the external density on the afterglow light curve by considering, for the first time, a full treatment of both the hydrodynamic evolution and the radiation in this scenario. To this end we develop a semi-analytic model for the light curve and carry out several elaborate numerical simulations using a one dimensional hydrodynamic code together with a synchrotron radiation code. Two spherically symmetric cases are explored in detail--a density jump in a uniform external medium, and a wind termination shock. The effect of density clumps is also constrained. Contrary to previous works, we find that even a very sharp (modeled as a step function) and large (by a factor of a >> 1) increase in the external density does not produce sharp features in the light curve, and cannot account for significant temporal variability in GRB afterglows. For a wind termination shock, the light curve smoothly transitions between the asymptotic power laws over about one …

The Department of Energy (DOE) identified the caustic side solvent extraction (CSSX) process as the preferred technology to remove cesium from radioactive waste solutions at the Savannah River Site (SRS). As a result, Washington Savannah River Company (WSRC) began designing and building a Modular CSSX Unit (MCU) in the SRS tank farm to process liquid waste for an interim period until the Salt Waste Processing Facility (SWPF) begins operations. Both the solvent and the strip effluent streams could contain high concentrations of cesium which must be removed from the contactors, process tanks, and piping prior to performing contactor maintenance. When these vessels are drained, thin films or drops will remain on the equipment walls. Following draining, the vessels will be flushed with water and drained to remove the flush water. The draining reduces the cesium concentration in the vessels by reducing the volume of cesium-containing material. The flushing, and subsequent draining, reduces the cesium in the vessels by diluting the cesium that remains in the film or drops on the vessel walls. MCU personnel requested that Savannah River National Laboratory (SRNL) researchers conduct a literature search to identify models to calculate the thickness of the liquid films remaining in the …

The International Atomic Energy Agency (IAEA) safeguards system has changed in major ways from the establishment of the IAEA in 1957 until the present. Changes include strengthening the legal framework of safeguards; improvements in concepts and approaches for safeguards implementation; and significant improvements in the technical tools available to inspectors. In this paper, we explore three broad areas related to strengthening safeguards authorities and institutions: integrated safeguards and State-Level Approaches; special inspections; and NPT withdrawal and the continuation of safeguards.

This scoping study describes the underlying data resources and an analysis tool for a demand response assessment specifically tailored toward the needs of the Modern Grid Initiatives Demonstration Field Test in Phase II in Morgantown, WV. To develop demand response strategies as part of more general distribution automation, automated islanding and feeder reconfiguration schemes, an assessment of the demand response resource potential is required. This report provides the data for the resource assessment for residential customers and describes a tool that allows the analyst to estimate demand response in kW for each hour of the day, by end-use, season, day type (weekday versus weekend) with specific saturation rates of residential appliances valid for the Morgantown, WV area.

The meeting began with presentations by the facilitator, Mr. Spiegel, and Dr. Lewis, the program director from DOE. The facilitator introduced those on the podium. He then described the general structure of the meeting and its purpose: to hear the issues and concerns of those present regarding the proposed Hawaiian Geothermal Project. He described his role in ensuring the impartiality and fairness of the meeting. Dr. Lewis further defined the scope of the project, introduced members of the EIS team, briefly described the EIS process, and answered several process questions, noting that cable feasibility would be examined and that Native Hawaiian concerns would be addressed. Ms. Borgstrom stated that the ISIS Implementation Plan will be continuously refined and that impacts of reasonably foreseeable future activities would be examined. During the meeting, more than 90% of the commenters requested that the EIS identify and assess the relative merits and impacts of energy alternatives to the proposed action. Nearly 80% requested that the EIS investigate conservation and renewable forms of energy, such as wind, solar, and biomass. They suggested that integrated resource planning should be used, noting that the State is initiating such a process. More than 30% of the commenters asked …

Large-Mach-number parallel plasma flows in the single-null SOL of different tokamaks are simulated with multi-fluid transport code UEDGE. The key role of poloidal asymmetry of cross-field plasma transport as the driving mechanism for such flows is discussed. The impact of ballooning-like diffusive and convective transport and plasma flows on divertor detachment, material migration, impurity flows, and erosion/deposition profiles is studied. The results on well-balanced double null plasma modeling that are indicative of strong asymmetry of cross-field transport are presented.

An IAEA Technical Meeting on Techniques for IAEA Verification of Enrichment Activities identified 'smart tags' as a technology that should be assessed for tracking and locating UF6 cylinders. Although there is vast commercial industry working on RFID systems, the vulnerabilities of commercial products are only beginning to emerge. Most of the commercially off-the-shelf (COTS) RFID systems operate in very narrow frequency bands, making them vulnerable to detection, jamming and tampering and also presenting difficulties when used around metals (i.e. UF6 cylinders). Commercial passive RFID tags have short range, while active RFID tags that provide long ranges have limited lifetimes. There are also some concerns with the introduction of strong (narrowband) radio frequency signals around radioactive and nuclear materials. Considering the shortcomings of commercial RFID systems, in their current form, they do not offer a promising solution for continuous monitoring and tracking of UF6 cylinders. In this paper, we identify the key challenges faced by commercial RFID systems for monitoring UF6 cylinders, and introduce an ultra-wideband approach for tag/reader communications that addresses most of the identified challenges for IAEA safeguards applications.

The main advantage of inverse iteration over the QR algorithm and Divide & Conquer for the symmetric tridiagonal eigenproblem is that subsets of eigenpairs can be computed at reduced cost. The MRRR algorithm (MRRR = Multiple Relatively Robust Representations) is a clever variant of inverse iteration without the need for reorthogonalization. STEGR, the current version of MRRR in LAPACK 3.0, does not allow for subset computations. The next release of STEGR is designed to compute a (sub-)set of k eigenpairs with {Omicron}(kn) operations. Because of the special way in which eigenvectors are computed, MRRR subset computations are more complicated than when using inverse iteration. Unlike the latter, MRRR sometimes cannot ignore the unwanted part of the spectrum. We describe the problems with what we call 'false singletons'. These are eigenvalues that appear to be isolated with respect to the wanted eigenvalues but in fact belong to a tight cluster of unwanted eigenvalues. This paper analyzes these complications and ways to deal with them.

Thermal degradation of a filled, crosslinked siloxane material synthesized from PDMS chains of three different average molecular weights and with two different crosslinking species has been studied by {sup 1}H Multiple Quantum (MQ) NMR methods. Multiple domains of polymer chains were detected by MQ NMR exhibiting Residual Dipolar Coupling (<{Omega}{sub d}>) values of 200 Hz and 600 Hz, corresponding to chains with high average molecular weight between crosslinks and chains with low average molecular weight between crosslinks or near the multifunctional crosslinking sites. Characterization of the <{Omega}{sub d}> values and changes in <{Omega}{sub d}> distributions present in the material were studied as a function of time at 250 C and indicates significant time dependent degradation. For the domains with low <{Omega}{sub d}>, a broadening in the distribution was observed with aging time. For the domain with high <{Omega}{sub d}>, increases in both the mean <{Omega}{sub d}> and the width in <{Omega}{sub d}> were observed with increasing aging time. Isothermal Thermal Gravimetric Analysis (TGA) reveals a 3% decrease in weight over 20 hours of aging at 250 C. Degraded samples also were analyzed by traditional solid state {sup 1}H NMR techniques and offgassing products were identified by Solid Phase MicroExtraction followed …